Improve handling of failed integer type conversions.

Source/bindings/v8/custom/V8PromiseCustom.cpp

Index: Source/bindings/v8/custom/V8PromiseCustom.cpp
diff --git a/Source/bindings/v8/custom/V8PromiseCustom.cpp b/Source/bindings/v8/custom/V8PromiseCustom.cpp
index 6c6a2431ec8a8050c037520fd3e9c79e46eb44d0..eeabb25ce2dbbde2fdceb4f9f0e2c878957ebce1 100644
--- a/Source/bindings/v8/custom/V8PromiseCustom.cpp
+++ b/Source/bindings/v8/custom/V8PromiseCustom.cpp
@@ -628,9 +628,8 @@ v8::Local<v8::Object> V8PromiseCustom::getInternal(v8::Handle<v8::Object> promis
 V8PromiseCustom::PromiseState V8PromiseCustom::getState(v8::Handle<v8::Object> internal)
 {
     v8::Handle<v8::Value> value = internal->GetInternalField(V8PromiseCustom::InternalStateIndex);
-    bool ok = false;
-    uint32_t number = toInt32(value, ok);
-    ASSERT(ok && (number == Pending || number == Fulfilled || number == Rejected || number == Following));
+    uint32_t number = toInt32(value);
+    ASSERT(number == Pending || number == Fulfilled || number == Rejected || number == Following);
     return static_cast<PromiseState>(number);
 }