Reland "Fix SkImageSource::filterBounds()"

This relands commit cb4d58766668b003fea67798027fc25d84acd059
which was reverted by commit b6d2be1330f16fe05f1eed5abda927c0fbb50055
because the original CL broke some blink layout tests.

This reland let SkImageSource::filterBounds() return the dst rect with
ctm applied regardless of direction.

Original description:

> Previously SkImageSource::filterBounds() uses the default
> SkImageFilter::onFilterNodeBounds() which returns the input rect.
>
> Now override onFilterNodeBounds() in SkImageSource to return src
> or dst rect (with transform applied).

Change-Id: I915b7889ff59829ddbc4479cd66d75a0bb581e54
Reviewed-on: https://skia-review.googlesource.com/47501
Commit-Queue: Stephen White <senorblanco@chromium.org>
Reviewed-by: Stephen White <senorblanco@chromium.org>
3 files changed