[run_web_tests] Let virtual tests inherit base tests' image first config

Previously, the behavior that a virtual test failed because of missing
txt result while the base test were passing suprised many developers and
took them much time to find out that the virtual test suite should be
added in LayoutTests/ImageFirstTests.

Change-Id: I03c6893a4aa7468cd4a327e84d1a4195124c45cb
Reviewed-on: https://chromium-review.googlesource.com/1058330
Commit-Queue: Xianzhu Wang <wangxianzhu@chromium.org>
Reviewed-by: Quinten Yearsley <qyearsley@chromium.org>
Cr-Commit-Position: refs/heads/master@{#558549}

third_party/WebKit/LayoutTests/ImageFirstTests

@@ -6,18 +6,6 @@ ietestcenter/css3/multicolumn
 ietestcenter/css3/grid
 http/tests/fullscreen
 tables
-tables/mozilla/marvin
-tables/mozilla/dom
-tables/mozilla/collapsing_borders
-tables/mozilla/core
-tables/mozilla/other
-tables/mozilla/bugs
-tables/mozilla_expected_failures/marvin
-tables/mozilla_expected_failures/dom
-tables/mozilla_expected_failures/collapsing_borders
-tables/mozilla_expected_failures/core
-tables/mozilla_expected_failures/other
-tables/mozilla_expected_failures/bugs
 fullscreen
 fonts
 css1/font_properties
@@ -39,18 +27,12 @@ fast/css/content
 fast/css-intrinsic-dimensions
 fast/pagination
 fast/multicol
-fast/multicol/vertical-rl/balancing
-fast/multicol/vertical-lr/balancing
 fast/dom/Document/CaretRangeFromPoint
 fast/dom/elementsFromPoint
 fast/replaced
 fast/borders
 fast/box-sizing
 fast/block
-fast/block/margin-collapse/block-inside-inline
-fast/block/positioning/vertical-rl
-fast/block/positioning/auto
-fast/block/positioning/vertical-lr
 fast/autoresize
 fast/scroll-behavior
 fast/table
@@ -74,10 +56,4 @@ external/wpt/html/rendering/non-replaced-elements/the-fieldset-element-0
 external/wpt/html/rendering/non-replaced-elements/the-hr-element-0
 external/wpt/html/rendering/non-replaced-elements/lists
 virtual/layout_ng/css2.1/20110323
-virtual/layout_ng/fast/block/basic
-virtual/layout_ng/fast/block/margin-collapse
-virtual/layout_ng/fast/block/float
 virtual/layout_ng/external/wpt/css/CSS2/linebox
-virtual/mojo-loading/fast/table
-virtual/disable-spv175/fast/borders
-virtual/disable-spv175/fast/multicol

third_party/blink/tools/blinkpy/web_tests/controllers/layout_test_runner.py

@@ -273,7 +273,7 @@ class Worker(object):
         else:
             test_input.should_run_pixel_test = self._port.should_run_as_pixel_test(test_input)
         test_input.should_run_pixel_test_first = (
-            self._port.should_run_pixel_test_first(test_input))
+            self._port.should_run_pixel_test_first(test_input.test_name))
 
     def _run_test(self, test_input, shard_name):
         self._batch_count += 1

third_party/blink/tools/blinkpy/web_tests/port/base.py

@@ -1754,9 +1754,15 @@ class Port(object):
             return False
         return True
 
-    def should_run_pixel_test_first(self, test_input):
-        return any(test_input.test_name.startswith(
-            directory) for directory in self._options.image_first_tests)
+    def should_run_pixel_test_first(self, test_name):
+        """Returns true if the directory of the test (or the base test if the
+           test is virtual) is listed in _options.image_first_tests (which comes
+           from LayoutTests/ImageFirstTests or the command line).
+        """
+        if any(test_name.startswith(directory) for directory in self._options.image_first_tests):
+            return True
+        base = self.lookup_virtual_test_base(test_name)
+        return base and self.should_run_pixel_test_first(base)
 
     def _build_path(self, *comps):
         """Returns a path from the build directory."""

third_party/blink/tools/blinkpy/web_tests/port/base_unittest.py

@@ -885,6 +885,23 @@ class PortTest(unittest.TestCase):
             'Bug(test) failures/expected/image.html [ WontFix ]\n')
         self.assertTrue(port.skips_test('failures/expected/image.html'))
 
+    def test_should_run_pixel_test_first(self):
+        port = self.make_port(port_name='foo')
+        # pylint: disable=protected-access
+        port._options.image_first_tests = ['image-first', 'virtual/flag/additional-virtual-image-first']
+        port.host.filesystem.write_text_file(
+            '/mock-checkout/third_party/WebKit/LayoutTests/VirtualTestSuites',
+            json.dumps([
+                { "prefix": "flag", "base": "image-first", "args": ["--flag"]},
+                { "prefix": "flag", "base": "non-image-first", "args": ["--flag"]}
+            ]))
+
+        self.assertTrue(port.should_run_pixel_test_first('image-first/test.html'))
+        self.assertTrue(port.should_run_pixel_test_first('virtual/flag/image-first/test.html'))
+        self.assertTrue(port.should_run_pixel_test_first('virtual/flag/additional-virtual-image-first/test.html'))
+        self.assertFalse(port.should_run_pixel_test_first('non-image-first/test.html'))
+        self.assertFalse(port.should_run_pixel_test_first('virtual/flag/non-image-first/test.html'))
+
 
 class NaturalCompareTest(unittest.TestCase):