That calls an unknown amount of Python code, and can do quite a bit of
work - especially if people do things like launch scripted processes in
this script affordance. Doing that while holding a major lock like the
ModuleList lock is asking for trouble.

I tried to make a test that would actually stall without this, but I
couldn't come up with anything that reliably failed. You always have to
get pretty unlucky.

Identical PR to: https://github.com/llvm/llvm-project/pull/134563
Previous PR was approved and landed but broke the build due to bad
merge.
Manually resolve the merge conflict and try to land again.

Co-authored-by: George Hu <georgehuyubo@gmail.com>

This reverts commit 070a4ae2f9bcf6967a7147ed2972f409eaa7d3a6.

Multiple buildbot failures have been reported:
https://github.com/llvm/llvm-project/pull/134563

The build fails with:

  lldb/source/Target/Statistics.cpp:75:39: error: use of undeclared
  identifier 'num_symbols_loaded'

In statistics, add locate time for each module in statistics, we time
the PluginManager::LocateExecutableSymbolFile and
PluginManager::LocateExecutableObjectFile call, save the duration for
the succeeded symbol locator plugin in the Module class as a map.
New key being added:
Module level: "_symbolLocatorTime_"
Summary level: "_totalSymbolLocatorTime_"
which would be a map of symbol_locator_plugin_name to time.

Sample statistic dump output after this change:

```
Command: statistics dump
===============Output===============
{
  "commands": {
    "command container add": 1,
    "command script add": 51,
    "command script import": 59,
    "statistics dump": 1,
    "target create": 1,
    "type summary add": 36,
    "type synthetic add": 21
  },
  "memory": {
    "strings": {
      "bytesTotal": 2801664,
      "bytesUnused": 1704256,
      "bytesUsed": 1097408
    }
  },
  "modules": [
    {
      "debugInfoByteSize": 244927,
      "debugInfoEnabled": true,
      "debugInfoHadIncompleteTypes": false,
      "debugInfoHadVariableErrors": false,
      "debugInfoIndexLoadedFromCache": false,
      "debugInfoIndexSavedToCache": false,
      "debugInfoIndexTime": 0.61934599999999995,
      "debugInfoParseTime": 0.00033100000000000002,
      "identifier": 94868115726768,
      "path": "/home/hyubo/.cache/llvm-debuginfod/client/llvmcache-720c9a0f5ba8b460a1524a25597226f0fa551f71-c4crasher",
      "symbolLocatorTime": {
        "debuginfod": 1.4547020000000002
      },
      "symbolTableIndexTime": 0.0035370000000000002,
      "symbolTableLoadedFromCache": false,
      "symbolTableParseTime": 0.0055040000000000002,
      "symbolTableSavedToCache": false,
      "symbolTableStripped": false,
      "triple": "x86_64--linux",
      "uuid": "720C9A0F-5BA8-B460-A152-4A25597226F0-FA551F71"
    },
    {
      "debugInfoByteSize": 0,
      "debugInfoEnabled": false,
      "debugInfoHadIncompleteTypes": false,
      "debugInfoHadVariableErrors": false,
      "debugInfoIndexLoadedFromCache": false,
      "debugInfoIndexSavedToCache": false,
      "debugInfoIndexTime": 0,
      "debugInfoParseTime": 0,
      "identifier": 94868111142256,
      "path": "[vdso](0x00007ffd41c59000)",
      "symbolLocatorTime": {
        "debuginfod": 0.80597700000000005
      },
      "symbolTableIndexTime": 2.8e-05,
      "symbolTableLoadedFromCache": false,
      "symbolTableParseTime": 0.00037300000000000001,
      "symbolTableSavedToCache": false,
      "symbolTableStripped": false,
      "triple": "x86_64--linux",
      "uuid": "4D1F38BD-BD34-DFB3-C9A5-B49A2A912219-AC713763"
    },
    {
      "debugInfoByteSize": 0,
      "debugInfoEnabled": false,
      "debugInfoHadIncompleteTypes": false,
      "debugInfoHadVariableErrors": false,
      "debugInfoIndexLoadedFromCache": false,
      "debugInfoIndexSavedToCache": false,
      "debugInfoIndexTime": 0,
      "debugInfoParseTime": 0,
      "identifier": 94868116162096,
      "path": "/usr/local/fbcode/platform010/lib/libc.so.6",
      "symbolLocatorTime": {
        "debuginfod": 0.286356
      },
      "symbolTableIndexTime": 0.0091780000000000004,
      "symbolTableLoadedFromCache": false,
      "symbolTableParseTime": 0.081841999999999998,
      "symbolTableSavedToCache": false,
      "symbolTableStripped": false,
      "triple": "x86_64--linux",
      "uuid": "ACE9DF01-8872-3A35-6D14-3C92527EF739-4BE32C75"
    },
    {
      "debugInfoByteSize": 0,
      "debugInfoEnabled": false,
      "debugInfoHadIncompleteTypes": false,
      "debugInfoHadVariableErrors": false,
      "debugInfoIndexLoadedFromCache": false,
      "debugInfoIndexSavedToCache": false,
      "debugInfoIndexTime": 0,
      "debugInfoParseTime": 0,
      "identifier": 94868111990032,
      "path": "/usr/local/fbcode/platform010/lib/libm.so.6",
      "symbolLocatorTime": {
        "debuginfod": 0.63356699999999999
      },
      "symbolTableIndexTime": 0.0023960000000000001,
      "symbolTableLoadedFromCache": false,
      "symbolTableParseTime": 0.021706,
      "symbolTableSavedToCache": false,
      "symbolTableStripped": false,
      "triple": "x86_64--linux",
      "uuid": "85932B54-0DE7-4FC1-23B0-FB09AD1A5A61-8E1098B7"
    },
    {
      "debugInfoByteSize": 0,
      "debugInfoEnabled": false,
      "debugInfoHadIncompleteTypes": false,
      "debugInfoHadVariableErrors": false,
      "debugInfoIndexLoadedFromCache": false,
      "debugInfoIndexSavedToCache": false,
      "debugInfoIndexTime": 0,
      "debugInfoParseTime": 0,
      "identifier": 94868116399488,
      "path": "/usr/local/fbcode/platform010/lib/libmvec.so.1",
      "symbolLocatorTime": {
        "debuginfod": 0.66705099999999995
      },
      "symbolTableIndexTime": 0.00053700000000000004,
      "symbolTableLoadedFromCache": false,
      "symbolTableParseTime": 0.0034429999999999999,
      "symbolTableSavedToCache": false,
      "symbolTableStripped": false,
      "triple": "x86_64--linux",
      "uuid": "4537CA22-8E6E-495B-7A03-FC2CEDCAD71C-8A7B2067"
    },
    {
      "debugInfoByteSize": 0,
      "debugInfoEnabled": false,
      "debugInfoHadIncompleteTypes": false,
      "debugInfoHadVariableErrors": false,
      "debugInfoIndexLoadedFromCache": false,
      "debugInfoIndexSavedToCache": false,
      "debugInfoIndexTime": 0,
      "debugInfoParseTime": 0,
      "identifier": 94868111778368,
      "path": "/usr/local/fbcode/platform010/lib/libatomic.so.1",
      "symbolLocatorTime": {
        "debuginfod": 0.83268299999999995
      },
      "symbolTableIndexTime": 0.000243,
      "symbolTableLoadedFromCache": false,
      "symbolTableParseTime": 0.0026640000000000001,
      "symbolTableSavedToCache": false,
      "symbolTableStripped": false,
      "triple": "x86_64--",
      "uuid": "F90F9111-BBD1-C2A9-972A-34EB75ABE62E-3BDED9CF"
    },
    {
      "debugInfoByteSize": 0,
      "debugInfoEnabled": false,
      "debugInfoHadIncompleteTypes": false,
      "debugInfoHadVariableErrors": false,
      "debugInfoIndexLoadedFromCache": false,
      "debugInfoIndexSavedToCache": false,
      "debugInfoIndexTime": 0,
      "debugInfoParseTime": 0,
      "identifier": 94868116403264,
      "path": "/usr/local/fbcode/platform010/lib/libgcc_s.so.1",
      "symbolLocatorTime": {
        "debuginfod": 0.58871499999999999
      },
      "symbolTableIndexTime": 0.000292,
      "symbolTableLoadedFromCache": false,
      "symbolTableParseTime": 0.0033,
      "symbolTableSavedToCache": false,
      "symbolTableStripped": false,
      "triple": "x86_64--",
      "uuid": "1C715A92-40BE-BE95-E148-1B401749BAB8-15D09F9D"
    },
    {
      "debugInfoByteSize": 0,
      "debugInfoEnabled": false,
      "debugInfoHadIncompleteTypes": false,
      "debugInfoHadVariableErrors": false,
      "debugInfoIndexLoadedFromCache": false,
      "debugInfoIndexSavedToCache": false,
      "debugInfoIndexTime": 0,
      "debugInfoParseTime": 0,
      "identifier": 94868113225328,
      "path": "/usr/local/fbcode/platform010/lib/libstdc++.so.6",
      "symbolLocatorTime": {
        "debuginfod": 0.76993400000000001
      },
      "symbolTableIndexTime": 0.042455,
      "symbolTableLoadedFromCache": false,
      "symbolTableParseTime": 0.081374000000000002,
      "symbolTableSavedToCache": false,
      "symbolTableStripped": false,
      "triple": "x86_64--",
      "uuid": "C9DAEE53-F607-981B-6BED-F2042833BFC7-71A1E66C"
    },
    {
      "debugInfoByteSize": 0,
      "debugInfoEnabled": false,
      "debugInfoHadIncompleteTypes": false,
      "debugInfoHadVariableErrors": false,
      "debugInfoIndexLoadedFromCache": false,
      "debugInfoIndexSavedToCache": false,
      "debugInfoIndexTime": 0,
      "debugInfoParseTime": 0,
      "identifier": 94868113600960,
      "path": "/usr/local/fbcode/platform010/lib/ld.so",
      "symbolLocatorTime": {
        "debuginfod": 0.48382199999999997
      },
      "symbolTableIndexTime": 0.00054799999999999998,
      "symbolTableLoadedFromCache": false,
      "symbolTableParseTime": 0.0057219999999999997,
      "symbolTableSavedToCache": false,
      "symbolTableStripped": false,
      "triple": "x86_64--linux",
      "uuid": "CCA86CF4-E4FF-42C8-7056-2F7D8B83AEE0-530B4095"
    }
  ],
  "targets": [
    {
      "breakpoints": [],
      "dyldPluginName": "dump-modulelist-dyld",
      "expressionEvaluation": {
        "failures": 0,
        "successes": 0
      },
      "frameVariable": {
        "failures": 0,
        "successes": 0
      },
      "mismatchCoredumpModuleCount": 0,
      "moduleIdentifiers": [
        94868115726768,
        94868111142256,
        94868116162096,
        94868111990032,
        94868116399488,
        94868111778368,
        94868116403264,
        94868113225328,
        94868113600960
      ],
      "signals": [
        {
          "SIGABRT": 1
        }
      ],
      "sourceMapDeduceCount": 0,
      "sourceRealpathAttemptCount": 0,
      "sourceRealpathCompatibleCount": 0,
      "stopCount": 1,
      "summaryProviderStatistics": [],
      "targetCreateTime": 4.1999999999999998e-05,
      "totalBreakpointResolveTime": 0,
      "totalSharedLibraryEventHitCount": 0
    }
  ],
  "totalDebugInfoByteSize": 244927,
  "totalDebugInfoEnabled": 1,
  "totalDebugInfoIndexLoadedFromCache": 0,
  "totalDebugInfoIndexSavedToCache": 0,
  "totalDebugInfoIndexTime": 0.61934599999999995,
  "totalDebugInfoParseTime": 0.00033100000000000002,
  "totalModuleCount": 9,
  "totalModuleCountHasDebugInfo": 1,
  "totalModuleCountWithIncompleteTypes": 0,
  "totalModuleCountWithVariableErrors": 0,
  "totalSymbolLocatorTime": {
    "debuginfod": 6.5228070000000002
  },
  "totalSymbolTableIndexTime": 0.059214000000000003,
  "totalSymbolTableParseTime": 0.205928,
  "totalSymbolTableStripped": 0,
  "totalSymbolTablesLoadedFromCache": 0,
  "totalSymbolTablesSavedToCache": 0,
  "transcript": [
    {
      "command": "symsrv",
      "commandArguments": "",
      "commandName": "symsrv",
      "durationInSeconds": 0.00069099999999999999,
      "error": "",
      "output": "",
      "timestampInEpochSeconds": 1744934015
    },
    {
      "command": "settings set symbols.enable-external-lookup true",
      "commandArguments": "symbols.enable-external-lookup true",
      "commandName": "settings set",
      "durationInSeconds": 4.1999999999999998e-05,
      "error": "",
      "output": "",
      "timestampInEpochSeconds": 1744934015
    },
    {
      "command": "settings insert-before plugin.symbol-locator.debuginfod.server-urls 0 https://our.intern.facebook.com/intern/debuginfod",
      "commandArguments": "plugin.symbol-locator.debuginfod.server-urls 0 https://our.intern.facebook.com/intern/debuginfod",
      "commandName": "settings insert-before",
      "durationInSeconds": 5.5999999999999999e-05,
      "error": "",
      "output": "",
      "timestampInEpochSeconds": 1744934015
    },
    {
      "command": "target create --core \"/var/tmp/cores/c4crasher.crasher.1576894\"",
      "commandArguments": "--core \"/var/tmp/cores/c4crasher.crasher.1576894\"",
      "commandName": "target create",
      "durationInSeconds": 6.7297630000000002,
      "error": "",
      "output": "Core file '/var/tmp/cores/c4crasher.crasher.1576894' (x86_64) was loaded.\n",
      "timestampInEpochSeconds": 1744934017
    },
    {
      "command": "fbpaste statistics dump",
      "commandArguments": "statistics dump",
      "commandName": "fbpaste",
      "timestampInEpochSeconds": 1744934055
    },
    {
      "command": "statistics dump",
      "commandArguments": "",
      "commandName": "statistics dump",
      "timestampInEpochSeconds": 1744934055
    }
  ]
}

```

Co-authored-by: George Hu <georgehuyubo@gmail.com>

This patch removes all of the Set.* methods from Status.

This cleanup is part of a series of patches that make it harder use the
anti-pattern of keeping a long-lives Status object around and updating
it while dropping any errors it contains on the floor.

This patch is largely NFC, the more interesting next steps this enables
is to:
1. remove Status.Clear()
2. assert that Status::operator=() never overwrites an error
3. remove Status::operator=()

Note that step (2) will bring 90% of the benefits for users, and step
(3) will dramatically clean up the error handling code in various
places. In the end my goal is to convert all APIs that are of the form

`    ResultTy DoFoo(Status& error)
`
to

`    llvm::Expected<ResultTy> DoFoo()
`
How to read this patch?

The interesting changes are in Status.h and Status.cpp, all other
changes are mostly

` perl -pi -e 's/\.SetErrorString/ = Status::FromErrorString/g' $(git
grep -l SetErrorString lldb/source)
`
plus the occasional manual cleanup.

LLDB has a setting (symbols.enable-background-lookup) that calls
dsymForUUID on a background thread for images as they appear in the
current backtrace. Originally, the laziness of only looking up symbols
for images in the backtrace only existed to bring the number of
dsymForUUID calls down to a manageable number.

Users have requesting the same functionality but blocking. This gives
them the same user experience as enabling dsymForUUID globally, but
without the massive upfront cost of having to download all the images,
the majority of which they'll likely not need.

This patch renames the setting to have a more generic name
(symbols.auto-download) and changes its values from a boolean to an
enum. Users can now specify "off", "background" and "foreground". The
default remains "off" although I'll probably change that in the near
future.

Reverts llvm/llvm-project#80890

LLDB has a setting (symbols.enable-background-lookup) that calls
dsymForUUID on a background thread for images as they appear in the
current backtrace. Originally, the laziness of only looking up symbols
for images in the backtrace only existed to bring the number of
dsymForUUID calls down to a manageable number.

Users have requesting the same functionality but blocking. This gives
them the same user experience as enabling dsymForUUID globally, but
without the massive upfront cost of having to download all the images,
the majority of which they'll likely not need.

This patch renames the setting to have a more generic name
(symbols.auto-download) and changes its values from a boolean to an
enum. Users can now specify "off", "background" and "foreground". The
default remains "off" although I'll probably change that in the near
future.

MS-STL warns about this with `warning STL4016: std::shared_ptr::unique() is deprecated in C++17`.