[llvm] Make llvm::telemetry::Manager::preDispatch protected. (PR #127114)

[LLVM Continuous Integration via llvm-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `sanitizer-x86_64-linux-android` running on `sanitizer-buildbot-android` while building `llvm` at step 2 "annotate".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/186/builds/6550

<details>
<summary>Here is the relevant piece of the build log for the reference</summary>

```
Step 2 (annotate) failure: 'python ../sanitizer_buildbot/sanitizers/zorg/buildbot/builders/sanitizers/buildbot_selector.py' (failure)
...
[578/5408] Linking CXX shared module lib/Bye.so
[579/5408] Linking CXX executable bin/llvm-undname
[580/5408] Linking CXX shared module unittests/Analysis/InlineOrderPlugin.so
[581/5408] Linking CXX shared module unittests/Analysis/InlineAdvisorPlugin.so
[582/5408] Linking CXX executable bin/llvm-opt-report
[583/5408] Linking CXX shared library lib/libRemarks.so.21.0git
[584/5408] Linking CXX shared module lib/ExampleIRTransforms.so
[585/5408] Linking CXX executable bin/reduce-chunk-list
[586/5408] Linking CXX executable bin/llvm-remarkutil
[587/5408] Building CXX object lib/Telemetry/CMakeFiles/LLVMTelemetry.dir/Telemetry.cpp.o
FAILED: lib/Telemetry/CMakeFiles/LLVMTelemetry.dir/Telemetry.cpp.o 
CCACHE_CPP2=yes CCACHE_HASHDIR=yes /usr/bin/ccache /var/lib/buildbot/sanitizer-buildbot6/sanitizer-x86_64-linux-android/build/llvm_build0/bin/clang++ -DGTEST_HAS_RTTI=0 -D_DEBUG -D_GLIBCXX_ASSERTIONS -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -I/var/lib/buildbot/sanitizer-buildbot6/sanitizer-x86_64-linux-android/build/llvm_build64/lib/Telemetry -I/var/lib/buildbot/sanitizer-buildbot6/sanitizer-x86_64-linux-android/build/llvm-project/llvm/lib/Telemetry -I/var/lib/buildbot/sanitizer-buildbot6/sanitizer-x86_64-linux-android/build/llvm_build64/include -I/var/lib/buildbot/sanitizer-buildbot6/sanitizer-x86_64-linux-android/build/llvm-project/llvm/include -fPIC -fno-semantic-interposition -fvisibility-inlines-hidden -Werror -Werror=date-time -Werror=unguarded-availability-new -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wmissing-field-initializers -pedantic -Wno-long-long -Wc++98-compat-extra-semi -Wimplicit-fallthrough -Wcovered-switch-default -Wno-noexcept-type -Wnon-virtual-dtor -Wdelete-non-virtual-dtor -Wsuggest-override -Wstring-conversion -Wmisleading-indentation -Wctad-maybe-unsupported -fdiagnostics-color -ffunction-sections -fdata-sections -O3 -DNDEBUG -std=c++17  -fno-exceptions -funwind-tables -fno-rtti -UNDEBUG -MD -MT lib/Telemetry/CMakeFiles/LLVMTelemetry.dir/Telemetry.cpp.o -MF lib/Telemetry/CMakeFiles/LLVMTelemetry.dir/Telemetry.cpp.o.d -o lib/Telemetry/CMakeFiles/LLVMTelemetry.dir/Telemetry.cpp.o -c /var/lib/buildbot/sanitizer-buildbot6/sanitizer-x86_64-linux-android/build/llvm-project/llvm/lib/Telemetry/Telemetry.cpp
In file included from /var/lib/buildbot/sanitizer-buildbot6/sanitizer-x86_64-linux-android/build/llvm-project/llvm/lib/Telemetry/Telemetry.cpp:14:
/var/lib/buildbot/sanitizer-buildbot6/sanitizer-x86_64-linux-android/build/llvm-project/llvm/include/llvm/Telemetry/Telemetry.h:152:52: error: non-void function does not return a value [-Werror,-Wreturn-type]
  152 |   virtual Error preDispatch(TelemetryInfo *Entry) {}
      |                                                    ^
1 error generated.
[588/5408] Building AArch64TargetParserDef.inc...
[589/5408] Building AArch64GenExegesis.inc...
[590/5408] Building AArch64GenCallingConv.inc...
[591/5408] Building AArch64GenMCPseudoLowering.inc...
[592/5408] Building AArch64GenMCCodeEmitter.inc...
[593/5408] Building AArch64GenDisassemblerTables.inc...
[594/5408] Building AArch64GenAsmWriter.inc...
[595/5408] Building AArch64GenAsmWriter1.inc...
[596/5408] Building AArch64GenAsmMatcher.inc...
[597/5408] Building AArch64GenFastISel.inc...
[598/5408] Building AArch64GenGlobalISel.inc...
[599/5408] Building AArch64GenDAGISel.inc...
[600/5408] Building AArch64GenInstrInfo.inc...
ninja: build stopped: subcommand failed.

How to reproduce locally: https://github.com/google/sanitizers/wiki/SanitizerBotReproduceBuild

@@@STEP_FAILURE@@@
Step 8 (bootstrap clang) failure: bootstrap clang (failure)
...
[578/5408] Linking CXX shared module lib/Bye.so
[579/5408] Linking CXX executable bin/llvm-undname
[580/5408] Linking CXX shared module unittests/Analysis/InlineOrderPlugin.so
[581/5408] Linking CXX shared module unittests/Analysis/InlineAdvisorPlugin.so
[582/5408] Linking CXX executable bin/llvm-opt-report
[583/5408] Linking CXX shared library lib/libRemarks.so.21.0git
[584/5408] Linking CXX shared module lib/ExampleIRTransforms.so
[585/5408] Linking CXX executable bin/reduce-chunk-list
[586/5408] Linking CXX executable bin/llvm-remarkutil
[587/5408] Building CXX object lib/Telemetry/CMakeFiles/LLVMTelemetry.dir/Telemetry.cpp.o
FAILED: lib/Telemetry/CMakeFiles/LLVMTelemetry.dir/Telemetry.cpp.o 
CCACHE_CPP2=yes CCACHE_HASHDIR=yes /usr/bin/ccache /var/lib/buildbot/sanitizer-buildbot6/sanitizer-x86_64-linux-android/build/llvm_build0/bin/clang++ -DGTEST_HAS_RTTI=0 -D_DEBUG -D_GLIBCXX_ASSERTIONS -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -I/var/lib/buildbot/sanitizer-buildbot6/sanitizer-x86_64-linux-android/build/llvm_build64/lib/Telemetry -I/var/lib/buildbot/sanitizer-buildbot6/sanitizer-x86_64-linux-android/build/llvm-project/llvm/lib/Telemetry -I/var/lib/buildbot/sanitizer-buildbot6/sanitizer-x86_64-linux-android/build/llvm_build64/include -I/var/lib/buildbot/sanitizer-buildbot6/sanitizer-x86_64-linux-android/build/llvm-project/llvm/include -fPIC -fno-semantic-interposition -fvisibility-inlines-hidden -Werror -Werror=date-time -Werror=unguarded-availability-new -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wmissing-field-initializers -pedantic -Wno-long-long -Wc++98-compat-extra-semi -Wimplicit-fallthrough -Wcovered-switch-default -Wno-noexcept-type -Wnon-virtual-dtor -Wdelete-non-virtual-dtor -Wsuggest-override -Wstring-conversion -Wmisleading-indentation -Wctad-maybe-unsupported -fdiagnostics-color -ffunction-sections -fdata-sections -O3 -DNDEBUG -std=c++17  -fno-exceptions -funwind-tables -fno-rtti -UNDEBUG -MD -MT lib/Telemetry/CMakeFiles/LLVMTelemetry.dir/Telemetry.cpp.o -MF lib/Telemetry/CMakeFiles/LLVMTelemetry.dir/Telemetry.cpp.o.d -o lib/Telemetry/CMakeFiles/LLVMTelemetry.dir/Telemetry.cpp.o -c /var/lib/buildbot/sanitizer-buildbot6/sanitizer-x86_64-linux-android/build/llvm-project/llvm/lib/Telemetry/Telemetry.cpp
In file included from /var/lib/buildbot/sanitizer-buildbot6/sanitizer-x86_64-linux-android/build/llvm-project/llvm/lib/Telemetry/Telemetry.cpp:14:
/var/lib/buildbot/sanitizer-buildbot6/sanitizer-x86_64-linux-android/build/llvm-project/llvm/include/llvm/Telemetry/Telemetry.h:152:52: error: non-void function does not return a value [-Werror,-Wreturn-type]
  152 |   virtual Error preDispatch(TelemetryInfo *Entry) {}
      |                                                    ^
1 error generated.
[588/5408] Building AArch64TargetParserDef.inc...
[589/5408] Building AArch64GenExegesis.inc...
[590/5408] Building AArch64GenCallingConv.inc...
[591/5408] Building AArch64GenMCPseudoLowering.inc...
[592/5408] Building AArch64GenMCCodeEmitter.inc...
[593/5408] Building AArch64GenDisassemblerTables.inc...
[594/5408] Building AArch64GenAsmWriter.inc...
[595/5408] Building AArch64GenAsmWriter1.inc...
[596/5408] Building AArch64GenAsmMatcher.inc...
[597/5408] Building AArch64GenFastISel.inc...
[598/5408] Building AArch64GenGlobalISel.inc...
[599/5408] Building AArch64GenDAGISel.inc...
[600/5408] Building AArch64GenInstrInfo.inc...
ninja: build stopped: subcommand failed.

How to reproduce locally: https://github.com/google/sanitizers/wiki/SanitizerBotReproduceBuild
program finished with exit code 2
elapsedTime=53.880285

```

</details>

https://github.com/llvm/llvm-project/pull/127114