Implement the gamepad API in the IPC proxy

content/common/gamepad_user_gesture.cc

+// Copyright (c) 2012 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 "content/common/gamepad_user_gesture.h"
+
+#include <algorithm>
+
+#include "third_party/WebKit/Source/WebKit/chromium/public/platform/WebGamepads.h"
+
+namespace content {
+
+bool GamepadsHaveUserGesture(const WebKit::WebGamepads& gamepads) {
+  for (unsigned i = 0; i < WebKit::WebGamepads::itemsLengthCap; i++) {
+    const WebKit::WebGamepad& pad = gamepads.items[i];
+
+    // If the device is physically connected, then check the primary 4 buttons
+    // to see if there is currently an intentional user action.
+    if (pad.connected) {
+      const unsigned kPrimaryInteractionButtons = 4;
+      unsigned buttons_to_check = std::min(pad.buttonsLength,
+                                           kPrimaryInteractionButtons);
+      for (unsigned button_index = 0; button_index < buttons_to_check;
+           button_index++) {
+        if (pad.buttons[button_index] > 0.5f)
+          return true;
+      }
+    }
+  }
+  return false;
+}
+
+}  // namespace content