Fix email address in trim_heap OWNERS file

google.com, not chromium.org.

Change-Id: Ic89c09bb251d09635f4d164706c8cc17984f7e2c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2145089Reviewed-by: Jesse McKenna <jessemckenna@google.com>
Commit-Queue: Bruce Dawson <brucedawson@chromium.org>
Cr-Commit-Position: refs/heads/master@{#758375}

tools/win/trim_heap/OWNERS

 brucedawson@chromium.org
 davidbienvenu@chromium.org
-jessemckenna@chromium.org
+jessemckenna@google.com