Disable content_shell_crash_tests on Win7 Tests (1).

It is failing, for unclear reasons. Disable to unblock the
CQ until someone can make it work again.

TBR=sandersd@chromium.org
NOTRY=true

Bug: 846729
Change-Id: I5bb455036799fbce53ae302ff5c3761d2da2a27e
Reviewed-on: https://chromium-review.googlesource.com/1072451Reviewed-by: Dirk Pranke <dpranke@chromium.org>
Commit-Queue: Dirk Pranke <dpranke@chromium.org>
Cr-Commit-Position: refs/heads/master@{#561902}

testing/buildbot/chromium.win.json

@@ -2375,13 +2375,6 @@
           "can_use_on_swarming_builders": true
         }
       },
-      {
-        "isolate_name": "content_shell_crash_test",
-        "name": "content_shell_crash_test",
-        "swarming": {
-          "can_use_on_swarming_builders": true
-        }
-      },
       {
         "isolate_name": "metrics_python_tests",
         "name": "metrics_python_tests",

testing/buildbot/test_suite_exceptions.pyl

@@ -924,6 +924,8 @@
       'Mac10.11 Tests',
       'Mac10.12 Tests',
       'Mac10.13 Tests (dbg)',
+      # crbug.com/846729 - re-enable when this passes reliably.
+      'Win7 Tests (1)',
       # On chromium.win, unclear why these only run on "Win7 Tests (1)".
       'Win 7 Tests x64 (1)',
       'Win10 Tests x64',