Fix GPU rasterization test flag

The --force-gpu-rasterization flag hasn't existed for a while but it's
still used by GPU tests that want to ensure GPU rasterization. Switch
the tests to use --enable-gpu-rasterization instead. I think this is
only an issue on Linux, since other platforms have GPU rasterization
enable by default, but some of the screenshot_sync and
pixel_skia_gold_tests will change how they run with this.

Bug: 1133368
Change-Id: I973d5ad6343d1e9d951a4854a98956fa09098387
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2437705Reviewed-by: Zhenyao Mo <zmo@chromium.org>
Commit-Queue: kylechar <kylechar@chromium.org>
Cr-Commit-Position: refs/heads/master@{#812809}

content/test/gpu/gpu_tests/common_browser_args.py

@@ -24,5 +24,5 @@ ENABLE_FORCE_FULL_DAMAGE = "--direct-composition-force-full-damage-for-testing"
 ENABLE_GPU_BENCHMARKING = '--enable-gpu-benchmarking'
 ENSURE_FORCED_COLOR_PROFILE = '--ensure-forced-color-profile'
 FORCE_COLOR_PROFILE_SRGB = '--force-color-profile=srgb'
-FORCE_GPU_RASTERIZATION = '--force-gpu-rasterization'
+ENABLE_GPU_RASTERIZATION = '--enable-gpu-rasterization'
 TEST_TYPE_GPU = '--test-type=gpu'

content/test/gpu/gpu_tests/pixel_test_pages.py

@@ -330,7 +330,7 @@ class PixelTestPages(object):
   @staticmethod
   def GpuRasterizationPages(base_name):
     browser_args = [
-        cba.FORCE_GPU_RASTERIZATION,
+        cba.ENABLE_GPU_RASTERIZATION,
         cba.DISABLE_SOFTWARE_COMPOSITING_FALLBACK,
     ]
     return [

content/test/gpu/gpu_tests/screenshot_sync_integration_test.py

@@ -90,9 +90,9 @@ class ScreenshotSyncIntegrationTest(gpu_integration_test.GpuIntegrationTest):
     yield ('ScreenshotSync_SWRasterWithDivs', 'screenshot_sync_divs.html',
            ('--disable-gpu-rasterization'))
     yield ('ScreenshotSync_GPURasterWithCanvas', 'screenshot_sync_canvas.html',
-           (cba.FORCE_GPU_RASTERIZATION))
+           (cba.ENABLE_GPU_RASTERIZATION))
     yield ('ScreenshotSync_GPURasterWithDivs', 'screenshot_sync_divs.html',
-           (cba.FORCE_GPU_RASTERIZATION))
+           (cba.ENABLE_GPU_RASTERIZATION))
 
   def _Navigate(self, test_path):
     url = self.UrlOfStaticFilePath(test_path)