Revert of Disable failing GPU tests on Nexus 6.

tools/dm_flags.py

 #
 # Copyright 2015 Google Inc.
 #
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 #
 
 #!/usr/bin/env python
 
 usage = '''
@@ skipping 122 matching lines @@
     blacklist.extend('pdf skp _ worldjournal'.split(' '))
     blacklist.extend('pdf skp _ desk_baidu.skp'.split(' '))
     blacklist.extend('pdf skp _ desk_wikipedia.skp'.split(' '))
 
   if 'iOS' in bot:
     blacklist.extend('gpu skp _ _ msaa skp _ _'.split(' '))
     blacklist.extend('gpu image decode _ msaa image decode _'.split(' '))
     blacklist.extend('gpu image subset _ msaa image subset _'.split(' '))
     blacklist.extend('msaa16 gm _ tilemodesProcess'.split(' '))
 
-  # Disabled until skbug.com/3942 is resolved.
-  if 'Nexus6' in bot:
-    blacklist.extend('_ tests _ WritePixels'.split(' '))
-    blacklist.extend('_ tests _ FloatingPointTextureTest'.split(' '))
-
   if blacklist:
     args.append('--blacklist')
     args.extend(blacklist)
 
   match = []
   if 'Valgrind' in bot: # skia:3021
     match.append('~Threaded')
   if 'TSAN' in bot: # skia:3562
     match.append('~Math')
 
@@ skipping 20 matching lines @@
 
 
 def self_test():
   import coverage  # This way the bots don't need coverage.py to be installed.
   args = {}
   cases = [
     'Pretend-iOS-Bot',
     'Test-Android-GCC-Nexus9-GPU-TegraK1-Arm64-Debug',
     'Test-Android-GCC-GalaxyS3-GPU-Mali400-Arm7-Debug',
     'Test-Android-GCC-GalaxyS4-GPU-SGX544-Arm7-Release',
-    'Test-Android-GCC-Nexus6-GPU-Adreno420-Arm7-Debug',
     'Test-Android-GCC-Nexus7-GPU-Tegra3-Arm7-Release',
     'Test-Android-GCC-NexusPlayer-CPU-SSSE3-x86-Release',
     'Test-Ubuntu-GCC-ShuttleA-GPU-GTX550Ti-x86_64-Release-Valgrind',
     'Test-Ubuntu-GCC-GCE-CPU-AVX2-x86_64-Release-TSAN',
     'Test-Ubuntu-GCC-GCE-CPU-AVX2-x86_64-Release-Valgrind',
     'Test-Win7-MSVC-ShuttleA-GPU-HD2000-x86-Debug-ANGLE',
   ]
 
   cov = coverage.coverage()
   cov.start()
@@ skipping 17 matching lines @@
   if len(sys.argv) == 2 and sys.argv[1] == 'test':
     self_test()
     sys.exit(0)
 
   if len(sys.argv) != 3:
     print usage
     sys.exit(1)
 
   with open(sys.argv[1], 'w') as out:
     json.dump(get_args(sys.argv[2]), out)