Install notion of diagnostic handler into PNaCl bitcode readers.

lib/Bitcode/NaCl/TestUtils/NaClBitcodeMunge.cpp

 //===--- Bitcode/NaCl/TestUtils/NaClBitcodeMunge.cpp - Bitcode Munger -----===//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
 // Bitcode writer/munger implementation for testing.
@@ skipping 123 matching lines @@
   return cleanupTest();
 }
 
 bool NaClParseBitcodeMunger::runTest(const uint64_t Munges[], size_t MungesSize,
                                      bool VerboseErrors) {
   bool AddHeader = true;
   if (!setupTest(Munges, MungesSize, AddHeader))
     return cleanupTest();
 
   LLVMContext &Context = getGlobalContext();
-
-  raw_ostream *VerboseStrm = VerboseErrors ? &getDumpStream() : nullptr;
   ErrorOr<Module *> ModuleOrError =
       NaClParseBitcodeFile(MungedInput->getMemBufferRef(), Context,
-                           VerboseStrm);
+                           redirectNaClDiagnosticToStream(getDumpStream()));
   if (ModuleOrError) {
     if (VerboseErrors)
       getDumpStream() << "Successful parse!\n";
     delete ModuleOrError.get();
   } else {
     Error() << ModuleOrError.getError().message() << "\n";
   }
   return cleanupTest();
 }
 
 bool NaClCompressMunger::runTest(const uint64_t Munges[], size_t MungesSize) {
   bool AddHeader = true;
   if (!setupTest(Munges, MungesSize, AddHeader))
     return cleanupTest();
 
   NaClBitcodeCompressor Compressor;
   if (!Compressor.compress(MungedInput.get(), getDumpStream()))
     Error() << "Unable to compress\n";
   return cleanupTest();
 }