[MIPS] Support for MIPS PNaCl in PPAPI

Add necessary definitions and build blocks for MIPS.

BUG= https://code.google.com/p/nativeclient/issues/detail?id=2275
TEST= Build Chromium for MIPS

Review URL: https://codereview.chromium.org/152133007

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@252416 0039d316-1c4b-4281-b951-d872f2087c98
Create DeviceMediaID for screen w/ correct 'id' value

When per-screen capture supported was added to WebRTC, the
MediaCaptureDevicesDispatcher was incorrectly set to request "screen:0"
rather than "screen" to capture the entire desktop, in effect.

BUG=343926

Review URL: https://codereview.chromium.org/171023007

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@252417 0039d316-1c4b-4281-b951-d872f2087c98
Allow default handling in WM_NCHITTEST to go through in the LegacyRenderWidgetHostHWND class
if the parent does not handle the message.

BUG=344775
TBR=cpu

Review URL: https://codereview.chromium.org/168693005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@252418 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 252418