Update Gamepad.axes / GamepadButton.value to match the latest specification

public/platform/WebGamepad.h

 // 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:
 //
 // 1. Redistributions of source code must retain the above copyright
 //    notice, this list of conditions and the following disclaimer.
 // 2. 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.
@@ skipping 20 matching lines @@
 #endif
 
 namespace blink {
 
 #pragma pack(push, 1)
 
 class WebGamepadButton {
 public:
     WebGamepadButton()
         : pressed(false)
+// FIXME(cdumez): Remove #ifdefs once chromium-side has been updated.
+#if defined(ENABLE_NEW_GAMEPAD_API)
+        , value(0.)
+#else
         , value(0.f)
+#endif
     {
     }
+#if defined(ENABLE_NEW_GAMEPAD_API)
+    WebGamepadButton(bool pressed, double value)
+#else
     WebGamepadButton(bool pressed, float value)
+#endif
         : pressed(pressed)
         , value(value)
     {
     }
     bool pressed;
+#if defined(ENABLE_NEW_GAMEPAD_API)
+    double value;
+#else
     float value;
+#endif
 };
 
 // This structure is intentionally POD and fixed size so that it can be shared
 // memory between hardware polling threads and the rest of the browser. See
 // also WebGamepads.h.
 class WebGamepad {
 public:
     static const size_t idLengthCap = 128;
     static const size_t mappingLengthCap = 16;
     static const size_t axesLengthCap = 16;
@@ skipping 16 matching lines @@
     WebUChar id[idLengthCap];
 
     // Monotonically increasing value referring to when the data were last
     // updated.
     unsigned long long timestamp;
 
     // Number of valid entries in the axes array.
     unsigned axesLength;
 
     // Normalized values representing axes, in the range [-1..1].
+#if defined(ENABLE_NEW_GAMEPAD_API)
+    double axes[axesLengthCap];
+#else
     float axes[axesLengthCap];
+#endif
 
     // Number of valid entries in the buttons array.
     unsigned buttonsLength;
 
     // Button states
     WebGamepadButton buttons[buttonsLengthCap];
 
     // Mapping type (for example "standard")
     WebUChar mapping[mappingLengthCap];
 };
 
 #if BLINK_IMPLEMENTATION
+#if defined(ENABLE_NEW_GAMEPAD_API)
+COMPILE_ASSERT(sizeof(WebGamepad) == 721, WebGamepad_has_wrong_size);
+#else
 COMPILE_ASSERT(sizeof(WebGamepad) == 529, WebGamepad_has_wrong_size);
 #endif
+#endif
 
 #pragma pack(pop)
 
 }
 
 #endif // WebGamepad_h