Start an empty interface OffScreenCanvas

third_party/WebKit/Source/core/html/canvas/OffScreenCanvas.cpp

Index: third_party/WebKit/Source/core/html/canvas/OffScreenCanvas.cpp
diff --git a/third_party/WebKit/Source/core/html/canvas/OffScreenCanvas.cpp b/third_party/WebKit/Source/core/html/canvas/OffScreenCanvas.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..76ab22b7c43ce9beba886c099f16134c3b758127
--- /dev/null
+++ b/third_party/WebKit/Source/core/html/canvas/OffScreenCanvas.cpp
@@ -0,0 +1,46 @@
+// Copyright 2015 The Chromium 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 "config.h"
+#include "core/html/canvas/OffScreenCanvas.h"
+
+#include "wtf/MathExtras.h"
+
+namespace blink {
+
+OffScreenCanvas* OffScreenCanvas::create(unsigned width, unsigned height)
+{
+    if (width > INT_MAX)

[Justin Novosad, 2015/12/03 19:06:11]

This condition is not necessary. it is implied in clampTo. Same thing for the
code below.  INT_MAX should go away from this file.

[xidachen, 2015/12/03 20:42:22]

Done.

+        width = clampTo<int>(width);
+    if (height > INT_MAX)
+        height = clampTo<int>(height);
+    return new OffScreenCanvas(IntSize(width, height));
+}
+
+void OffScreenCanvas::setWidth(unsigned width)
+{
+    if (width > INT_MAX)
+        m_size.setWidth(clampTo<int>(width));
+    else
+        m_size.setWidth(width);
+}
+
+void OffScreenCanvas::setHeight(unsigned height)
+{
+    if (height > INT_MAX)
+        m_size.setHeight(clampTo<int>(height));
+    else
+        m_size.setHeight(height);
+}
+
+OffScreenCanvas::OffScreenCanvas(const IntSize& size)
+    : m_size(size)
+{
+}
+
+DEFINE_TRACE(OffScreenCanvas)
+{
+}
+
+} // namespace blink