Re-enable viz_browser_tests on Windows

There were capacity issues when we last added viz_browser_tests to Windows.
However based on discussions in https://crbug.com/829187 there appears to be
capacity on Win7 Tests (dbg)(1). This change re-eanbles them
on that config.

TEST=viz_browser_tests

Bug: 851631
Change-Id: Ie5f33ee667097faf0a1aadc3b5e23b85b2bd1aca
Reviewed-on: https://chromium-review.googlesource.com/1096078
Commit-Queue: Jonathan Ross <jonross@chromium.org>
Reviewed-by: Stephen Martinis <martiniss@chromium.org>
Cr-Commit-Position: refs/heads/master@{#567638}

testing/buildbot/chromium.win.json

@@ -2738,6 +2738,18 @@
         },
         "test": "browser_tests"
       },
+      {
+        "args": [
+          "--enable-features=VizDisplayCompositor",
+          "--test-launcher-filter-file=../../testing/buildbot/filters/viz.browser_tests.filter"
+        ],
+        "name": "viz_browser_tests",
+        "swarming": {
+          "can_use_on_swarming_builders": true,
+          "shards": 10
+        },
+        "test": "browser_tests"
+      },
       {
         "swarming": {
           "can_use_on_swarming_builders": true

testing/buildbot/test_suite_exceptions.pyl

@@ -2354,7 +2354,6 @@
       'Win 7 Tests x64 (1)',
       'Win10 Tests x64',
       'Win7 Tests (1)',
-      'Win7 Tests (dbg)(1)',
       'Win10 Tests x64 (dbg)',
     ],
     'modifications': {