First version of PerformanceObserver

Source/bindings/core/v8/custom/V8PerformanceCustom.cpp

+/*
+ * Copyright (C) 2015 Google Inc. All rights reserved.

[esprehn, 2015/07/18 22:24:15]

Please use the short copyright in all your files.

[MikeB, 2015/07/20 23:06:50]

Done.

+ *
+ * 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
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "config.h"
+#include "bindings/core/v8/V8Performance.h"
+
+#include "bindings/core/v8/ExceptionMessages.h"
+#include "bindings/core/v8/ExceptionState.h"
+#include "bindings/core/v8/V8Binding.h"
+#include "bindings/core/v8/V8DOMWrapper.h"
+#include "bindings/core/v8/V8GCController.h"
+#include "bindings/core/v8/V8PerformanceObserverCallback.h"
+#include "core/timing/DOMWindowPerformance.h"
+#include "core/timing/PerformanceObserver.h"
+
+namespace blink {
+
+void V8Performance::createPerformanceObserverMethodCustom(const v8::FunctionCallbackInfo<v8::Value>& info)

[esprehn, 2015/07/18 22:24:15]

hmm, does this really need to be custom? The code generator has come a very long
way since we made MutationObservers. If this still needs to be custom you should
file a bug and assign to haraken@/Cr-Blink-Bindings so we can get it fixed.

[MikeB, 2015/07/20 23:06:50]

I couldn't get code generator to correctly do line 58. It would either create a
blink::ScriptValue, which couldn't cast to PerformanceObserverCallback* or try
and call PerformanceObserverCallback::toImplWithTypeCheck which doesn't exist. 
The problem goes away if I can skip the custom V8PerformanceObserverCallback.

+{
+    if (UNLIKELY(info.Length() < 1)) {
+        V8ThrowException::throwException(createMinimumArityTypeErrorForMethod(info.GetIsolate(), "createPerformanceObserver", "Performance", 1, info.Length()), info.GetIsolate());
+        return;
+    }
+    Performance* impl = V8Performance::toImpl(info.Holder());
+    PerformanceObserverCallback* callback;
+    {
+        if (info.Length() <= 0 || !info[0]->IsFunction()) {
+            V8ThrowException::throwTypeError(info.GetIsolate(), ExceptionMessages::failedToExecute("createPerformanceObserver", "Performance", "The callback provided as parameter 1 is not a function."));
+            return;
+        }
+        callback = V8PerformanceObserverCallback::create(v8::Local<v8::Function>::Cast(info[0]), ScriptState::current(info.GetIsolate()));
+    }
+    v8SetReturnValue(info, impl->createPerformanceObserver(callback));
+}
+
+} // namespace blink