bindings: make toImplArguments() less strict

Source/bindings/core/v8/V8Binding.h

 /*
 * Copyright (C) 2009 Google Inc. All rights reserved.
 * Copyright (C) 2012 Ericsson AB. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *     * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
@@ skipping 987 matching lines @@
         result.uncheckedAppend(TraitsType::nativeValue(element, isolate, exceptionState));
         if (exceptionState.hadException())
             return Vector<T>();
     }
     return result;
 }
 
 template <class T>
 Vector<T> toImplArguments(const v8::FunctionCallbackInfo<v8::Value>& info, int startIndex, ExceptionState& exceptionState)
 {
-    ASSERT(startIndex <= info.Length());
     Vector<T> result;
     typedef NativeValueTraits<T> TraitsType;
     int length = info.Length();
-    result.reserveInitialCapacity(length);
-    for (int i = startIndex; i < length; ++i) {
-        result.uncheckedAppend(TraitsType::nativeValue(info[i], info.GetIsolate(), exceptionState));
-        if (exceptionState.hadException())
-            return Vector<T>();
+    if (startIndex < length) {
+        result.reserveInitialCapacity(length - startIndex);
+        for (int i = startIndex; i < length; ++i) {
+            result.uncheckedAppend(TraitsType::nativeValue(info[i], info.GetIsolate(), exceptionState));
+            if (exceptionState.hadException())
+                return Vector<T>();
+        }
     }
     return result;
 }
 
 // Validates that the passed object is a sequence type per WebIDL spec
 // http://www.w3.org/TR/2012/CR-WebIDL-20120419/#es-sequence
 inline bool toV8Sequence(v8::Handle<v8::Value> value, uint32_t& length, v8::Isolate* isolate, ExceptionState& exceptionState)
 {
     // Attempt converting to a sequence if the value is not already an array but is
     // any kind of object except for a native Date object or a native RegExp object.
@@ skipping 231 matching lines @@
 v8::Local<v8::Value> v8IteratorResult(ScriptState* scriptState, const T& value)
 {
     return v8IteratorResult(scriptState->isolate(), V8ValueTraits<T>::toV8Value(value, scriptState->context()->Global(), scriptState->isolate()));
 }
 
 typedef void (*InstallTemplateFunction)(v8::Handle<v8::FunctionTemplate>, v8::Isolate*);
 
 } // namespace blink
 
 #endif // V8Binding_h