Revert "Clang support for -flto=thin." (bot failures)

Rolling this back for now since there are a couple of bot failures on
the new tests I added, and I won't have a chance to look at them in detail
until later this afternoon. I think the new tests need some restrictions on
having the gold plugin available.

This reverts commit r250398.

llvm-svn: 250402

clang/lib/CodeGen/BackendUtil.cpp

@@ -605,8 +605,8 @@ void EmitAssemblyHelper::EmitAssembly(BackendAction Action,
     break;
 
   case Backend_EmitBC:
-    getPerModulePasses()->add(createBitcodeWriterPass(
-        *OS, CodeGenOpts.EmitLLVMUseLists, CodeGenOpts.EmitFunctionSummary));
+    getPerModulePasses()->add(
+        createBitcodeWriterPass(*OS, CodeGenOpts.EmitLLVMUseLists));
     break;
 
   case Backend_EmitLL: