Revert of Roll ANGLE. (patchset #1 id:1 of https://codereview.chromium.org/579903002/)

Reason for revert:
Appears to be causing build failures. Here's an example.
http://build.chromium.org/p/chromium.gpu.fyi/builders/GPU%20Win%20Builder%20%28dbg%29/builds/12428/steps/steps/logs/stdio

Original issue's description:
> Roll ANGLE.
>
> Contains fixes for setting sampler uniforms.
>
> BUG=414450
>
> Committed: https://crrev.com/ee4fc3e3db62b0a19e39f575b8faecd2dcc2f88b
> Cr-Commit-Position: refs/heads/master@{#295519}

TBR=vmiura@chromium.org,geofflang@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=414450

Review URL: https://codereview.chromium.org/585593002

Cr-Commit-Position: refs/heads/master@{#295529}

DEPS

@@ -51,7 +51,7 @@ vars = {
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling ANGLE
   # and whatever else without interference from each other.
-  "angle_revision": "af875527dd30df822016ff90307de938195176c3",
+  "angle_revision": "bbffd5562e33a6cf6f6f1bb5be6cfa30df8f36ec",
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling build tools
   # and whatever else without interference from each other.