[PATCH] Correctly implement -include search logic.

[Richard Smith]

LGTM

================
Comment at: lib/Frontend/InitPreprocessor.cpp:69
@@ -72,1 +68,3 @@
+static void AddImplicitInclude(MacroBuilder &Builder, StringRef File) {
+  Builder.append(Twine("#include \"") + File + "\"");
 }
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Please include a comment here indicating that header search will search the current working directory for includes in the buffer.

http://reviews.llvm.org/D4823