Fix diff_resource_sizes.py import error

Fixes diff_resource_sizes.py failing to import build_utils after
https://crrev.com/c/1536068 by importing from the top level gyp
directory instead of directly from the util subdirectory.

Bug: 952908
Change-Id: I2fe75471f39b1acb758ba4a012e03fb52d1a4991
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1568790
Reviewed-by: Andrew Grieve <[email protected]>
Commit-Queue: Brian Sheedy <[email protected]>
Cr-Commit-Position: refs/heads/master@{#651344}
1 file changed