"This patch uses the new ObjCImplDecl class to merge Sema::ImplMethodsVsClassMethods...

"This patch uses the new ObjCImplDecl class to merge  Sema::ImplMethodsVsClassMethods and Sema::ImplCategoryMethodsVsIntfMethods methods.
And now, when clang check a class implementation to find unimplemented methods, it also checks all methods from the class extensions (unnamed categories).

There is also a test case to check this warning.

This patch contains also a minor update for ObjCImplDecl . getNameAsCString and getNameAsString now returns an empty string instead of crashing for unnamed categories."

Patch by Jean-Daniel Dupas!

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@65744 91177308-0d34-0410-b5e6-96231b3b80d8