[lldb][NFC] Remove unused/misnamed SetObjectModificationTime

[kastiglione]

Summary

Remove SetObjectModificationTime which is not currently used, and assigns to the wrong member.

[aprantl]

Sometimes these odd leaf APIs are used by custom downstream variants of LLDB, but without any comment pointing into that direction and no unit test, I think this makes sense to remove. Also, we can easily add it back in later.

[JDevlieghere]

Nice

[kastiglione]

In D86493#2236454, @aprantl wrote:

Sometimes these odd leaf APIs are used by custom downstream variants of LLDB

I wondered about other consumers, how often is it the case that mainline lldb has code used only downstream?

[aprantl]

The largest downstream LLDB fork that I know about is swift-lldb, which is also open source and thus easy to check. There also exists a Rust version, and many custom forks for various specialized hardware. Putting patches up for review here gives the maintainers a chance to voice their concerns. For larger architectural changes we usually have a thread on lldb-dev to make sure we captured everyone's attention. We're under no obligation to not break anyone's private fork, but if there is an easy/reasonable way to make everyone happy we usually tend to choose that path.

[aprantl]

I should also mention that we are actively looking into ways to upstream the swift-lldb code into llvm.org. Now that both branches are licensed under Apache the only challenge left is to make the Swift support a real language *plugin* that can be conditionally compiled.

lldb/include/lldb/Core/Module.h

public:
   const llvm::sys::TimePoint<> &GetModificationTime() const {
     return m_mod_time;
   }
 
   const llvm::sys::TimePoint<> &GetObjectModificationTime() const {
     return m_object_mod_time;
   }
 
-  void SetObjectModificationTime(const llvm::sys::TimePoint<> &mod_time) {
-    m_mod_time = mod_time;
-  }
-
   /// This callback will be called by SymbolFile implementations when
   /// parsing a compile unit that contains SDK information.
   /// \param sysroot will be added to the path remapping dictionary.
   void RegisterXcodeSDK(llvm::StringRef sdk, llvm::StringRef sysroot);
 
   /// Tells whether this module is capable of being the main executable for a
   /// process.
   ///