[Fuchsia] Enable blink web tests on Fuchsia x64 bots

Also:
1. Removed --qemy-require-kvm flag from the runner script since
run_web_tests.py doesn't support that flag. Instead KVM requirement is
handled by the runner script directly.
2. Disabled sharding when running layout tests on Fuchsia, including on
FYI bots: it doesn't make much sense to shard these tests since we run
only smoke tests and sharding overhead is comparable to the time it
takes to run all tests on a single bot.

Bug: 778467
Change-Id: Ice7a11ebf5c51c84550745e8e88cd71cd300b0fd
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1549585
Commit-Queue: Sergey Ulanov <[email protected]>
Reviewed-by: John Budorick <[email protected]>
Reviewed-by: Kevin Marshall <[email protected]>
Cr-Commit-Position: refs/heads/master@{#649323}
diff --git a/testing/buildbot/test_suite_exceptions.pyl b/testing/buildbot/test_suite_exceptions.pyl
index 489171d..5c4e840 100644
--- a/testing/buildbot/test_suite_exceptions.pyl
+++ b/testing/buildbot/test_suite_exceptions.pyl
@@ -1573,6 +1573,9 @@
         'args': [
           '--platform=fuchsia',
         ],
+        'swarming': {
+          'shards': 1,
+        },
       },
       'linux-blink-animation-use-time-delta': {
         'args': [
@@ -1650,6 +1653,14 @@
         ],
       },
       # chromium.linux
+      'Fuchsia x64': {
+        'args': [
+          '--platform=fuchsia',
+        ],
+        'swarming': {
+          'shards': 1,
+        },
+      },
       'Linux Tests': {
         'swarming': {
           'dimension_sets': [