[mac] Mark keys with cmd pressed as isSystemKeys.

webkit/api/src/mac/WebInputEventFactory.mm

 /*
  * Copyright (C) 2004, 2006, 2007 Apple Inc. All rights reserved.
  * Copyright (C) 2006-2009 Google Inc.
  *
  * 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
@@ skipping 901 matching lines @@
         [unmodifiedStr getCharacters:&result.unmodifiedText[0]];
     } else
         ASSERT_NOT_REACHED();
 
     [identifierStr getCString:&result.keyIdentifier[0]
                     maxLength:sizeof(result.keyIdentifier)
                      encoding:NSASCIIStringEncoding];
 
     result.timeStampSeconds = [event timestamp];
 
+    // Windows and Linux set that if alt is down. WebKit looks at this to decide
+    // if it should handle a key or not. E.g. alt-left/right shouldn't be used
+    // by webkit to scroll the current page, because we want to get that key
+    // back for it to do history navigation. Hence, the corresponding situation
+    // on OS X is to set this for cmd key presses.
+    if (result.modifiers & WebInputEvent::MetaKey)
+        result.isSystemKey = true;
+
     return result;
 }
 
 WebKeyboardEvent WebInputEventFactory::keyboardEvent(wchar_t character,
                                                      int modifiers,
                                                      double timeStampSeconds)
 {
     // keyboardEvent(NSEvent*) depends on the NSEvent object and
     // it is hard to use it from methods of the NSTextInput protocol. For
     // such methods, this function creates a WebInputEvent::Char event without
     // using a NSEvent object.
     WebKeyboardEvent result;
     result.type = WebKit::WebInputEvent::Char;
     result.timeStampSeconds = timeStampSeconds;
     result.modifiers = modifiers;
     result.windowsKeyCode = character;
     result.nativeKeyCode = character;
     result.text[0] = character;
     result.unmodifiedText[0] = character;
+
+    // Windows and Linux set that if alt is down. WebKit looks at this to decide
+    // if it should handle a key or not. E.g. alt-left/right shouldn't be used
+    // by webkit to scroll the current page, because we want to get that key
+    // back for it to do history navigation. Hence, the corresponding situation
+    // on OS X is to set this for cmd key presses.
+    if (result.modifiers & WebInputEvent::MetaKey)
+        result.isSystemKey = true;
+
     return result;
 }
 
 // WebMouseEvent --------------------------------------------------------------
 
 WebMouseEvent WebInputEventFactory::mouseEvent(NSEvent* event, NSView* view)
 {
     WebMouseEvent result;
 
     result.clickCount = 0;
@@ skipping 219 matching lines @@
         result.deltaX = [event deltaX] * scrollbarPixelsPerCocoaTick;
         result.deltaY = [event deltaY] * scrollbarPixelsPerCocoaTick;
     }
 
     result.timeStampSeconds = [event timestamp];
 
     return result;
 }
 
 } // namespace WebKit