Reduce includes of some SVG*TearOff types

SVG*TearOff types are only of real interest to the bindings, so don't
need to be included in something that isn't direclty interacting with
bindings. Shuffle declarations and definitions to reduce the impact of
SVGPointTearOff and SVGRectTearOff.

Review-Url: https://codereview.chromium.org/2361973003
Cr-Commit-Position: refs/heads/master@{#420920}
6 files changed