Space key doesn't work in AURA enabled build because in case of space key,

ui/aura/desktop_host_linux.cc

 // Copyright (c) 2011 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 "ui/aura/desktop_host.h"
 
 #include <X11/cursorfont.h>
 #include <X11/Xlib.h>
 
 // Get rid of a macro from Xlib.h that conflicts with Aura's RootWindow class.
@@ skipping 177 matching lines @@
   if ((keycode >= ui::VKEY_0 && keycode <= ui::VKEY_9) ||
       (keycode >= ui::VKEY_A && keycode <= ui::VKEY_Z) ||
       (keycode >= ui::VKEY_NUMPAD0 && keycode <= ui::VKEY_NUMPAD9)) {
     return true;
   }
 
   switch (keycode) {
     case ui::VKEY_BACK:
     case ui::VKEY_RETURN:
     case ui::VKEY_ESCAPE:
+    case ui::VKEY_SPACE:
     case ui::VKEY_TAB:
     // In addition to the keys listed at MSDN, we include other
     // graphic-character and numpad keys.
     case ui::VKEY_MULTIPLY:
     case ui::VKEY_ADD:
     case ui::VKEY_SUBTRACT:
     case ui::VKEY_DECIMAL:
     case ui::VKEY_DIVIDE:
     case ui::VKEY_OEM_1:
     case ui::VKEY_OEM_2:
@@ skipping 280 matching lines @@
   return new DesktopHostLinux(bounds);
 }
 
 // static
 gfx::Size DesktopHost::GetNativeDisplaySize() {
   ::Display* xdisplay = base::MessagePumpX::GetDefaultXDisplay();
   return gfx::Size(DisplayWidth(xdisplay, 0), DisplayHeight(xdisplay, 0));
 }
 
 }  // namespace aura