Fix key missing problem on windows
Fix key missing problem on windows

Initialize INPUT struct. The dwFlags member of INPUT struct is not properly
initialized so sometimes the key event is interpreted as a key up and thus
keys are missed.

BUG=70167
TEST=keyboard input is fine on windows

Review URL: http://codereview.chromium.org/6542015

git-svn-id: http://src.chromium.org/svn/trunk/src@75385 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: 194d261720caaba53d6d1785e36c138d4b1a0991
meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser