Run breakpad_integration_test with WebAssemblyTrapHandler enabled

This test make sure that breakpad generates a crash dump when the renderer
crashes. We also need to ensure crash reports are generated when WebAssembly is
using trap-based bounds checks, as WebAssembly's attempts to recover from SEGV
signals could prevent crash reports from being generated.

Bug: chromium:722585
Change-Id: I152a6a1d6d0f91590c4e0fb0acfcce866064399d
Reviewed-on: https://chromium-review.googlesource.com/661785


Reviewed-by: Jochen Eisinger <jochen@chromium.org>
Commit-Queue: Eric Holk <eholk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#501366}