Adds ADD_FAILURE_AT (by Zhanyong Wan); disables -Wswitch-default (by Vlad Losev).

include/gtest/gtest.h

@@ -1627,6 +1627,12 @@ const T* TestWithParam<T>::parameter_ = NULL;
 // Generates a nonfatal failure with a generic message.
 #define ADD_FAILURE() GTEST_NONFATAL_FAILURE_("Failed")
 
+// Generates a nonfatal failure at the given source file location with
+// a generic message.
+#define ADD_FAILURE_AT(file, line) \
+  GTEST_MESSAGE_AT_(file, line, "Failed", \
+                    ::testing::TestPartResult::kNonFatalFailure)
+
 // Generates a fatal failure with a generic message.
 #define GTEST_FAIL() GTEST_FATAL_FAILURE_("Failed")