Disable a few clang-tidy checks by default.

The goal is to be able to run clang-tidy on LLVM files without further
configuration for now. Once llvm.org/PR19306 is addressed, we can add a
configuration file instead and choose other defaults.

llvm-svn: 205407

clang-tools-extra/clang-tidy/tool/ClangTidyMain.cpp

@@ -34,7 +34,11 @@ static cl::opt<std::string> Checks(
 static cl::opt<std::string> DisableChecks(
     "disable-checks",
     cl::desc("Regular expression matching the names of the checks to disable."),
-    cl::init("clang-analyzer-alpha.*"), cl::cat(ClangTidyCategory));
+    cl::init("(clang-analyzer-alpha.*" // To many false positives.
+             "|llvm-include-order"     // Not implemented yet.
+             "|llvm-namespace-comment" // Not complete.
+             "|google-.*"),            // Doesn't apply to LLVM.
+    cl::cat(ClangTidyCategory));
 static cl::opt<bool> Fix("fix", cl::desc("Fix detected errors if possible."),
                          cl::init(false), cl::cat(ClangTidyCategory));