Remove values from WebPreferences that are set by RenderViewImpl

The WebSettings corresponding to these bools:
 accelerated_compositing_for_overflow_scroll_enabled
 accelerated_compositing_for_scrollable_frames_enabled
 composited_scrolling_for_frames_enabled

Are set by RenderViewImpl::Initialize and by
RenderViewImpl::SetDeviceScaleFactor taking into account the device scale,
command line flags and platform.  These values were additionally being
set by WebPreferences based on only the command line flags in the
browser process. The browser process' version was obviously not
consistent with the value computed by RenderViewImpl as it did not have
access to all of the same information.  This caused two problems:

1.) The value applied whenever the WebPreferences changed and were applied to
the view did not match the desired value that RenderViewImpl computed 2.) The
settings changed in ways that Blink did not expect

In particular for this bug, the values computed by RenderViewImpl on a retina
mac would all be "true".  However when changing the font size the browser would
send down a new WebPreferences struct with these bits set to "false" which
RenderViewImpl::OnUpdateWebPreferences would apply to Blink. Changing the value
of composited_scrolling_for_frames_enabled would then cause Blink's bookkeeping
for a formerly composited scrollable frame to go haywire.

The fix is to remove these from WebPreferences and let
RenderViewImpl::{Initialize,SetDeviceScaleFactor} take care of setting the right
values.

BUG=346622

Review URL: https://codereview.chromium.org/183853012

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@254702 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 254702
Fixes possible crash in HWNDMessageHandler

Need to handle the possibility of this being deleted during dispatch

BUG=347861
TEST=see bug
R=ben@chromium.org

Review URL: https://codereview.chromium.org/185453002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@254703 0039d316-1c4b-4281-b951-d872f2087c98
Fix broken IPC fuzzer link once again.

TBR=inferno@chromium.org
TBR=mbarbella@chromium.org

Review URL: https://codereview.chromium.org/185593009

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@254704 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 254704
Rename to ChromiumTestShell package from testshell to shell

Rename org.chromium.chrome.testshell to org.chromium.chrome.shell
Move res/ directory to chrome/android/shell/res/

BUG=348137
TBR=pfeldman,craigdh

Review URL: https://codereview.chromium.org/184493006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@254705 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 254705