Pass the -Wmissing-declarations warning.

This makes it easier to use GTest in projects that build with the
-Wmissing-declarations warning. This fixes the warning in headers and
source files, though not GTest's own tests as it is rather noisy there.

googlemock/include/gmock/gmock-matchers.h

@@ -3615,6 +3615,10 @@ BoundSecondMatcher<Tuple2Matcher, Second> MatcherBindSecond(
   return BoundSecondMatcher<Tuple2Matcher, Second>(tm, second);
 }
 
+// Joins a vector of strings as if they are fields of a tuple; returns
+// the joined string.  This function is exported for testing.
+GTEST_API_ string JoinAsTuple(const Strings& fields);
+
 // Returns the description for a matcher defined using the MATCHER*()
 // macro where the user-supplied description string is "", if
 // 'negation' is false; otherwise returns the description of the

googlemock/src/gmock-spec-builders.cc

@@ -508,7 +508,7 @@ bool UntypedFunctionMockerBase::VerifyAndClearExpectationsLocked()
   return expectations_met;
 }
 
-CallReaction intToCallReaction(int mock_behavior) {
+static CallReaction intToCallReaction(int mock_behavior) {
   if (mock_behavior >= kAllow && mock_behavior <= kFail) {
     return static_cast<internal::CallReaction>(mock_behavior);
   }

googlemock/test/gmock-matchers_test.cc

@@ -65,10 +65,6 @@
 
 namespace testing {
 
-namespace internal {
-GTEST_API_ string JoinAsTuple(const Strings& fields);
-}  // namespace internal
-
 namespace gmock_matchers_test {
 
 using std::greater;