Mojo C++ bindings: make String16 and gfx::Size available in Blink

third_party/WebKit/Source/platform/mojo/CommonCustomTypesStructTraits.cpp

Index: third_party/WebKit/Source/platform/mojo/CommonCustomTypesStructTraits.cpp
diff --git a/third_party/WebKit/Source/platform/mojo/CommonCustomTypesStructTraits.cpp b/third_party/WebKit/Source/platform/mojo/CommonCustomTypesStructTraits.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..a66290f23b8a3af2cf5e8e3bd448a5e6933a75c2
--- /dev/null
+++ b/third_party/WebKit/Source/platform/mojo/CommonCustomTypesStructTraits.cpp
@@ -0,0 +1,41 @@
+// Copyright 2016 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 "platform/mojo/CommonCustomTypesStructTraits.h"
+
+#include "base/strings/latin1_string_conversions.h"
+#include <cstring>
+
+namespace mojo {
+
+// static
+WTF::Vector<uint16_t>
+StructTraits<mojo::common::mojom::String16DataView, ::WTF::String>::data(
+    const ::WTF::String& str) {
+  // TODO(zqzhang): Need to find a way to avoid another memory copy here. A
+  // broader is question is that should sending String16 over mojo be avoided?
+  // See https://crbug.com/653209
+
+  base::string16 str16 = base::Latin1OrUTF16ToUTF16(
+      str.length(), str.is8Bit() ? str.characters8() : nullptr /* latin1 */,
+      str.is8Bit() ? nullptr : str.characters16() /* utf16 */);
+  WTF::Vector<uint16_t> rawData(str16.size());
+  memcpy(rawData.data(), str16.data(), str16.size() * sizeof(uint16_t));
+  return rawData;
+}
+
+// static
+bool StructTraits<mojo::common::mojom::String16DataView, ::WTF::String>::Read(
+    mojo::common::mojom::String16DataView data,
+    ::WTF::String* out) {
+  mojo::ArrayDataView<uint16_t> view;
+  data.GetDataDataView(&view);
+  if (view.is_null())
+    return false;
+  *out =
+      ::WTF::String(reinterpret_cast<const UChar*>(view.data()), view.size());
+  return true;
+}
+
+}  // namespace mojo