bindings: Use Maybe APIs in V8ScriptRunner (part 1)

Source/bindings/core/v8/NPV8Object.cpp

Index: Source/bindings/core/v8/NPV8Object.cpp
diff --git a/Source/bindings/core/v8/NPV8Object.cpp b/Source/bindings/core/v8/NPV8Object.cpp
index 6db91ed61db76b81029da21c1b54e55dcfe49624..c547ed24d4e3c6b5964915b88d4827ac3768af2b 100644
--- a/Source/bindings/core/v8/NPV8Object.cpp
+++ b/Source/bindings/core/v8/NPV8Object.cpp
@@ -555,8 +555,9 @@ bool _NPN_Enumerate(NPP npp, NPObject* npObject, NPIdentifier** identifier, uint
             "  return props;"
             "});";
         v8::Handle<v8::String> source = v8AtomicString(isolate, enumeratorCode);
-        v8::Handle<v8::Value> result = V8ScriptRunner::compileAndRunInternalScript(source, isolate);
-        ASSERT(!result.IsEmpty());
+        v8::Local<v8::Value> result;
+        if (!V8ScriptRunner::compileAndRunInternalScript(source, isolate).ToLocal(&result))

[dcarney, 2015/03/13 08:15:45]

use macros to remove the if(!whatever) block in most places.  if you don't the
code will quickly become unreadable. we had the same problem in the v8 runtime

[bashi, 2015/03/17 02:01:36]

We discussed how we handle ToLocal failure, and we reached a consensus that we
don't use macros. https://codereview.chromium.org/970403003/

Macros can't improve readability these cases.

+            return false;
         ASSERT(result->IsFunction());
         v8::Handle<v8::Function> enumerator = v8::Handle<v8::Function>::Cast(result);
         v8::Handle<v8::Value> argv[] = { obj };