Remove SetJavaScriptFlags() wrapper function from webkit.

This function is just an helper/wrapper function around v8::V8::SetFlagsFromString() and used only by content.

John preferred to just remove the wrapper and call the v8 API directly in content.

Also removing it from webkit_glue.h helps with the removal of src/webkit/ directory.

BUG=265753
TEST=content_shell and content_unittests
R=jochen@chromium.org, jam@chromium.org
TBR=darin

Review URL: https://codereview.chromium.org/147973002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@247626 0039d316-1c4b-4281-b951-d872f2087c98
Fix UAF in WebSocketDispatcherHost

If Send() fails in SendOrDrop(), then |message| will have been deleted,
but SendOrDrop() will still try to access its header fields.

Fixed.

BUG=338354
TEST=content_unittests

Review URL: https://codereview.chromium.org/148263009

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@247627 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 247627