Fix DevTools support of worklets

third_party/WebKit/Source/core/inspector/MainThreadDebugger.cpp

 /*
  * Copyright (c) 2011 Google Inc. 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.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 170 matching lines @@
 {
     FrameConsole::unmute();
 }
 
 bool MainThreadDebugger::callingContextCanAccessContext(v8::Local<v8::Context> calling, v8::Local<v8::Context> target)
 {
     ExecutionContext* executionContext = toExecutionContext(target);
     ASSERT(executionContext);
 
     if (executionContext->isMainThreadWorkletGlobalScope()) {
-        MainThreadWorkletGlobalScope* globalScope = toMainThreadWorkletGlobalScope(executionContext);
-        return globalScope && BindingSecurity::shouldAllowAccessTo(m_isolate, toLocalDOMWindow(toDOMWindow(calling)), globalScope, DoNotReportSecurityError);
+        // Similar to WorkerThreadDebugger::callingContextCanAccessContext(http://crrev.com/1638563002).

[dgozman, 2016/06/13 13:14:06]

We can return |true| in workers just because we know that it's isolate contains
only a single worker, so any access is allowed. Here in main thread isolate, we
may have a lot of different pages (possibly with worklets), so access check is
required. I think, we should retrieve a LocalDOMWindow for both calling and
target regardless of whether they are worklets or not, and then ask
BindingSecurity.

+        return true;
     }
 
     DOMWindow* window = toDOMWindow(target);
     return window && BindingSecurity::shouldAllowAccessTo(m_isolate, toLocalDOMWindow(toDOMWindow(calling)), window, DoNotReportSecurityError);
 }
 
 int MainThreadDebugger::ensureDefaultContextInGroup(int contextGroupId)
 {
     LocalFrame* frame = WeakIdentifierMap<LocalFrame>::lookup(contextGroupId);
     if (!frame)
@@ skipping 142 matching lines @@
                 return;
             if (!nodes->Set(context, index++, toV8(node, info.Holder(), info.GetIsolate())).FromMaybe(false))
                 return;
         }
         info.GetReturnValue().Set(nodes);
     }
     exceptionState.throwIfNeeded();
 }
 
 } // namespace blink