Fix compile error on x86-generic (32-bit) PFQ bots.

For some reason the integer literal "1ULL" is still treated as 32-bit and we
encounter the error "left shift count >= width of type".

See x86-generic nightly chromium PFQ build #2727 for details.

BUG=none
TEST=trybot
R=satorux@chromium.org

Review URL: https://codereview.chromium.org/17175020

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@207976 0039d316-1c4b-4281-b951-d872f2087c98

chrome/browser/chromeos/audio/audio_devices_pref_handler_impl.cc

@@ -22,7 +22,7 @@ namespace {
 
 std::string GetDeviceIdString(const chromeos::AudioDevice& device) {
   return device.display_name + " : " +
-         base::Uint64ToString((device.id & ((1ULL << 32) - 1)));
+         base::Uint64ToString(device.id & static_cast<uint64>(0xffffffff));
 }
 
 }