binidngs: Make callInternalFunction return MaybeLocal

Source/bindings/core/v8/ScriptRegexp.cpp

Index: Source/bindings/core/v8/ScriptRegexp.cpp
diff --git a/Source/bindings/core/v8/ScriptRegexp.cpp b/Source/bindings/core/v8/ScriptRegexp.cpp
index 50389d1dc8aff0fd05abbf5d1cf9ae6a58599b10..8e1fa5fdb2020ec58d2b00bfe16a576a57417d1a 100644
--- a/Source/bindings/core/v8/ScriptRegexp.cpp
+++ b/Source/bindings/core/v8/ScriptRegexp.cpp
@@ -78,9 +78,8 @@ int ScriptRegexp::match(const String& string, int startFrom, int* matchLength) c
     v8::Local<v8::RegExp> regex = m_regex.newLocal(isolate);
     v8::Local<v8::Function> exec = regex->Get(v8AtomicString(isolate, "exec")).As<v8::Function>();
     v8::Local<v8::Value> argv[] = { v8String(isolate, string.substring(startFrom)) };
-    v8::Local<v8::Value> returnValue = V8ScriptRunner::callInternalFunction(exec, regex, WTF_ARRAY_LENGTH(argv), argv, isolate);
-
-    if (tryCatch.HasCaught())
+    v8::Local<v8::Value> returnValue;
+    if (!V8ScriptRunner::callInternalFunction(exec, regex, WTF_ARRAY_LENGTH(argv), argv, isolate).ToLocal(&returnValue))

[yurys, 2015/03/25 12:21:48]

I don't quite understand what's the advantage of returning MaybeLocal(which will
in most cases be followed by ToLocal) compared to calling IsEmpty() on the
result handle, can you please explain? Given that users can end up with an empty
Local handle after calling ToLocal I don't see a big improvement over inserting
IsEmpty() checks at all places where we get Local handle. Is it just to help
find all places where Local handle is used in potentially exception unsafe
manner?

         return -1;
 
     // RegExp#exec returns null if there's no match, otherwise it returns an