Enable SwiftShader fallback on desktop Linux.

content/test/gpu/gpu_tests/gpu_process_expectations.py

 # Copyright 2013 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 from gpu_tests.gpu_test_expectations import GpuTestExpectations
 
 # See the GpuTestExpectations class for documentation.
 
 class GpuProcessExpectations(GpuTestExpectations):
   def SetExpectations(self):
     # Accelerated 2D canvas is not available on Linux due to driver instability
     self.Fail('GpuProcess_canvas2d', ['linux'], bug=254724)
 
     self.Fail('GpuProcess_video', ['linux'], bug=257109)
 
     # Chrome on Android doesn't support software fallback.
     self.Skip('GpuProcess_no_gpu_process', ['android'], bug=643282)
     self.Skip('GpuProcess_skip_gpu_process', ['android'], bug=(610951, 610023))
 
-    # Chrome on Windows creates a GPU process that uses SwiftShader when using
-    # either --disable-gpu or a blacklisted GPU.
+    # Chrome on Windows and Linux create a GPU process that uses SwiftShader
+    # when using either --disable-gpu or a blacklisted GPU.
     self.Skip('GpuProcess_no_gpu_process', ['win', 'debug'], bug=630728)
-    self.Skip('GpuProcess_skip_gpu_process', ['win'], bug=630728)
+    self.Skip('GpuProcess_skip_gpu_process', ['win', 'linux'], bug=630728)
 
-    # Currently SwiftShader's integrated only on Windows. Remove
-    # platforms from this suppression as it is integrated on more
-    # platforms.
+    # Currently SwiftShader is integrated only on Windows and Linux. Remove
+    # platforms from this suppression as it is integrated on more platforms.
     self.Skip('GpuProcess_swiftshader_for_webgl',
-              ['mac', 'linux', 'android', 'chromeos'], bug=630728)
+              ['mac', 'android', 'chromeos'], bug=630728)
 
     # There is no Android multi-gpu configuration and the helper
     # gpu_info_collector.cc::IdentifyActiveGPU is not even called.
     self.Skip('GpuProcess_identify_active_gpu1', ['android'])
     self.Skip('GpuProcess_identify_active_gpu2', ['android'])
     self.Skip('GpuProcess_identify_active_gpu3', ['android'])
     self.Skip('GpuProcess_identify_active_gpu4', ['android'])
 
     # There is currently no entry in kSoftwareRenderingListJson that enables
     # a software GL driver on Android.
     self.Skip('GpuProcess_software_gpu_process', ['android'])
 
     # Seems to have become flaky on Windows recently.
     self.Flaky('GpuProcess_only_one_workaround', ['win'], bug=700522)