[PATCH] [clang-tidy] Move -extra-arg handling to CommonOptionsProvider

[Manuel Klimek]

LG. I prefer the current version.

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Comment at: lib/Tooling/CommonOptionsParser.cpp:82
@@ +81,3 @@
+  std::vector<CompileCommand> getAllCompileCommands() const override {
+    return Compilations->getAllCompileCommands();
+  }
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Do we also have to adjust here?

http://reviews.llvm.org/D6073