mac: Add browser tests for history swiping.

One of the tests replays recorded events from a real swipe.  The others
simulate realistic conditions and test edge cases. The tests discovered two
bugs:
- History swiping cannot be triggered if the very first touch event consists of
only vertical motion.
- History swiping blocks vertical part of diagonal swipes.

BUG=375514, 375512

Review URL: https://codereview.chromium.org/282143002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@272334 0039d316-1c4b-4281-b951-d872f2087c98

chrome/chrome_tests.gypi

@@ -1869,9 +1869,11 @@
           'dependencies': [
             'chrome',
             '../components/components.gyp:breakpad_stubs',
+            '../third_party/ocmock/ocmock.gyp:ocmock',
           ],
           'sources': [
             'browser/renderer_host/chrome_render_widget_host_view_mac_delegate_browsertest.cc',
+            'browser/renderer_host/chrome_render_widget_host_view_mac_history_swiper_browsertest.mm',
             'browser/spellchecker/spellcheck_message_filter_mac_browsertest.cc',
           ],
           'sources!': [