Fix uninitialized variable compiler errors [GCC 4.8.4]

src/api.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/api.h"
 
 #include <string.h>  // For memcpy, strlen.
 #ifdef V8_USE_ADDRESS_SANITIZER
 #include <sanitizer/asan_interface.h>
 #endif  // V8_USE_ADDRESS_SANITIZER
@@ skipping 3643 matching lines @@
   return true;
 }
 
 
 namespace {
 
 i::MaybeHandle<i::Object> DeleteObjectProperty(
     i::Isolate* isolate, i::Handle<i::JSReceiver> receiver,
     i::Handle<i::Object> key, i::LanguageMode language_mode) {
   // Check if the given key is an array index.
-  uint32_t index;
+  uint32_t index = 0;
   if (key->ToArrayIndex(&index)) {
     // In Firefox/SpiderMonkey, Safari and Opera you can access the
     // characters of a string using [] notation.  In the case of a
     // String object we just need to redirect the deletion to the
     // underlying string if the index is in range.  Since the
     // underlying string does nothing with the deletion, we can ignore
     // such deletions.
     if (receiver->IsStringObjectWithCharacterAt(index)) {
       return isolate->factory()->false_value();
     }
@@ skipping 290 matching lines @@
   return Delete(context, key).FromMaybe(false);
 }
 
 
 Maybe<bool> v8::Object::Has(Local<Context> context, Local<Value> key) {
   PREPARE_FOR_EXECUTION_PRIMITIVE(context, "v8::Object::Get()", bool);
   auto self = Utils::OpenHandle(this);
   auto key_obj = Utils::OpenHandle(*key);
   Maybe<bool> maybe = Nothing<bool>();
   // Check if the given key is an array index.
-  uint32_t index;
+  uint32_t index = 0;
   if (key_obj->ToArrayIndex(&index)) {
     maybe = i::JSReceiver::HasElement(self, index);
   } else {
     // Convert the key to a name - possibly by calling back into JavaScript.
     i::Handle<i::Name> name;
     if (i::Runtime::ToName(isolate, key_obj).ToHandle(&name)) {
       maybe = i::JSReceiver::HasProperty(self, name);
     }
   }
   has_pending_exception = maybe.IsNothing();
@@ skipping 4400 matching lines @@
   Address callback_address =
       reinterpret_cast<Address>(reinterpret_cast<intptr_t>(callback));
   VMState<EXTERNAL> state(isolate);
   ExternalCallbackScope call_scope(isolate, callback_address);
   callback(info);
 }
 
 
 }  // namespace internal
 }  // namespace v8