Revert of [DevTools] Add offset and scale to WebDeviceEmulationParams. (https://codereview.chromium.org/342953003/)

Reason for revert:
Broke compile.

Original issue's description:
> [DevTools] Add offset and scale to WebDeviceEmulationParams.
> 
> This will be used to set offset/scale from DevTools protocol
> instead of caluculating them in embedder.
> 
> BUG=327641
> NOTRY=true
> 
> Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=176506

TBR=pfeldman@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=327641

Review URL: https://codereview.chromium.org/342963002

git-svn-id: svn://svn.chromium.org/blink/trunk@176507 bbb929c8-8fbe-4397-9dbb-9b2b20218538