Switch PCHReader::getOriginalSourceFile to use proper diagnostics.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@90434 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Frontend/CompilerInvocation.cpp b/lib/Frontend/CompilerInvocation.cpp
index ccf60fb..2ecbcfe 100644
--- a/lib/Frontend/CompilerInvocation.cpp
+++ b/lib/Frontend/CompilerInvocation.cpp
@@ -1205,11 +1205,9 @@
     // PCH is handled specially, we need to extra the original include path.
     if (it->getOption().matches(OPT_include_pch)) {
       std::string OriginalFile =
-        PCHReader::getOriginalSourceFile(it->getValue(Args));
-
-      // FIXME: Don't fail like this.
+        PCHReader::getOriginalSourceFile(it->getValue(Args), Diags);
       if (OriginalFile.empty())
-        exit(1);
+        continue;
 
       Opts.Includes.push_back(OriginalFile);
     } else