Use v8::TryCatch in toImplSequence

third_party/WebKit/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 807 matching lines @@
       result.uncheckedAppend(
           TraitsType::nativeValue(info.GetIsolate(), info[i], exceptionState));
       if (exceptionState.hadException())
         return VectorType();
     }
   }
   return result;
 }
 
 // Gets an iterator from an Object.
-CORE_EXPORT v8::MaybeLocal<v8::Object> getEsIterator(v8::Isolate*,
-                                                     v8::Local<v8::Object>,
-                                                     ExceptionState&);
+CORE_EXPORT v8::Local<v8::Object> getEsIterator(v8::Isolate*,
+                                                v8::Local<v8::Object>,
+                                                ExceptionState&);
 
 // 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::Local<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 171 matching lines @@
                           v8::Local<v8::Value> value,
                           ExceptionState& exceptionState) {
   using ValueType = typename VectorType::ValueType;
 
   if (!value->IsObject() || value->IsRegExp()) {
     exceptionState.throwTypeError(
         "The provided value cannot be converted to a sequence.");
     return VectorType();
   }
 
-  v8::Local<v8::Object> iterator;
-  if (!getEsIterator(isolate, value.As<v8::Object>(), exceptionState)
-           .ToLocal(&iterator))
+  v8::TryCatch block(isolate);
+  v8::Local<v8::Object> iterator =
+      getEsIterator(isolate, value.As<v8::Object>(), exceptionState);
+  if (exceptionState.hadException())
     return VectorType();
 
   v8::Local<v8::String> nextKey = v8String(isolate, "next");
   v8::Local<v8::String> valueKey = v8String(isolate, "value");
   v8::Local<v8::String> doneKey = v8String(isolate, "done");
   v8::Local<v8::Context> context = isolate->GetCurrentContext();
   VectorType result;
   while (true) {
     v8::Local<v8::Value> next;
-    if (!iterator->Get(context, nextKey).ToLocal(&next))
+    if (!iterator->Get(context, nextKey).ToLocal(&next)) {
+      exceptionState.rethrowV8Exception(block.Exception());
       return VectorType();
+    }
     // TODO(bashi): Support callable objects.
     if (!next->IsObject() || !next.As<v8::Object>()->IsFunction()) {
       exceptionState.throwTypeError("Iterator.next should be callable.");
       return VectorType();
     }
     v8::Local<v8::Value> nextResult;
     if (!V8ScriptRunner::callFunction(next.As<v8::Function>(),
                                       toExecutionContext(context), iterator, 0,
                                       nullptr, isolate)
-             .ToLocal(&nextResult))
+             .ToLocal(&nextResult)) {
+      exceptionState.rethrowV8Exception(block.Exception());
       return VectorType();
+    }
     if (!nextResult->IsObject()) {
       exceptionState.throwTypeError(
           "Iterator.next() did not return an object.");
       return VectorType();
     }
     v8::Local<v8::Object> resultObject = nextResult.As<v8::Object>();
     v8::Local<v8::Value> element;
     v8::Local<v8::Value> done;
     if (!resultObject->Get(context, valueKey).ToLocal(&element) ||
-        !resultObject->Get(context, doneKey).ToLocal(&done))
+        !resultObject->Get(context, doneKey).ToLocal(&done)) {
+      exceptionState.rethrowV8Exception(block.Exception());
       return VectorType();
+    }
     v8::Local<v8::Boolean> doneBoolean;
-    if (!done->ToBoolean(context).ToLocal(&doneBoolean))
+    if (!done->ToBoolean(context).ToLocal(&doneBoolean)) {
+      exceptionState.rethrowV8Exception(block.Exception());
       return VectorType();
+    }
     if (doneBoolean->Value())
       break;
     result.append(NativeValueTraits<ValueType>::nativeValue(isolate, element,
                                                             exceptionState));
   }
   return result;
 }
 
 // If the current context causes out of memory, JavaScript setting
 // is disabled and it returns true.
@@ skipping 78 matching lines @@
 
 // Freeze a V8 object. The type of the first parameter and the return value is
 // intentionally v8::Value so that this function can wrap toV8().
 // If the argument isn't an object, this will crash.
 CORE_EXPORT v8::Local<v8::Value> freezeV8Object(v8::Local<v8::Value>,
                                                 v8::Isolate*);
 
 }  // namespace blink
 
 #endif  // V8Binding_h