[PATCH] Consistently handle clang-tidy check names in ClangTidyError.

[Daniel Jasper]

================
Comment at: clang-tidy/ClangTidyDiagnosticConsumer.cpp:278
@@ -270,1 +277,3 @@
 
+    if (CheckName.empty()) {
+      switch (DiagLevel) {
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So, this is true if Context.getCheckName(Info.getID()) returns "", right? In which cases does this happen?

================
Comment at: clang-tidy/ClangTidyDiagnosticConsumer.cpp:296
@@ -273,2 +295,3 @@
         DiagLevel == DiagnosticsEngine::Fatal) {
+      // Don't mute Clang errors regardless of filters and non-user code.
       Level = ClangTidyError::Error;
----------------
nit: "Don't mute" does not seem to be exactly what this does. It seems to be more of a "Force reporting of".

http://reviews.llvm.org/D4356