Webview apk_merger.py: Ignore classes3.dex.

Some debug builds of Webview have 3 dex files now.

Bug: 966542
Change-Id: Ib636f086042d2eb02f08f3390993594650f501b5
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1627662
Reviewed-by: Richard Coles <torne@chromium.org>
Commit-Queue: Eric Stevenson <estevenson@chromium.org>
Cr-Commit-Position: refs/heads/master@{#662771}
1 file changed