Pre-emptive fix for upcoming ANGLE change.

define angle_standalone = false, so that we can use that in
re-landing chromium-review.googlesource.com/c/angle/angle/+/2587451.

BUG: angleproject:5462
Change-Id: I810623b6d55735aac6d5ba5ad813aba0f32f9801
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/351496
Commit-Queue: Mike Klein <mtklein@google.com>
Reviewed-by: Mike Klein <mtklein@google.com>
1 file changed