webkit: Fix build in ISO C++ 11 mode

Change-Id: I32b3121ae46678f847dcd74ea74484aaf8f34eaf
Signed-off-by: Bernhard Rosenkraenzer <Bernhard.Rosenkranzer@linaro.org>
Merge branch 'linaro_android_4.2.1' of http://android.git.linaro.org/git-ro/platform/external/webkit into jb-mv-wip