Fix a FORWARD_NULL defect reported by Coverity.
Fix a FORWARD_NULL defect reported by Coverity.

In ChromeClientImpl::focus(), we need to do a null check
for 'delegate' before calling
delegate->FocusAccessibilityObject().

R=klink
BUG=http://crbug.com/17101
TEST=none
Review URL: http://codereview.chromium.org/159182

git-svn-id: dd90618784b6a4b323ea0c23a071cb1c9e6f2ac7@21296 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser