Add platform/transforms pretty printers for logging and testing

third_party/WebKit/Source/platform/blink_platform.gypi

 {
   'includes': [
     'platform_generated.gypi',
   ],
   'variables': {
     'platform_files': [
       'AsyncFileSystemCallbacks.h',
       'CalculationValue.h',
       'CheckedInt.h',
       'ContentDecryptionModuleResult.h',
@@ skipping 1332 matching lines @@
       'testing/TreeTestHelpers.h',
       'text/BidiResolverTest.cpp',
       'text/CharacterTest.cpp',
       'text/DateTimeFormatTest.cpp',
       'text/HyphenationTest.cpp',
       'text/SegmentedStringTest.cpp',
       'text/TextBreakIteratorTest.cpp',
       'text/TextEncodingDetectorTest.cpp',
       'text/UnicodeUtilitiesTest.cpp',
       'threading/BackgroundTaskRunnerTest.cpp',
+      'transforms/AffineTransformTest.cpp',
       'transforms/TransformOperationsTest.cpp',
-      'transforms/TransformTestHelper.h',
       'transforms/TransformationMatrixTest.cpp',
       'transforms/RotationTest.cpp',
       'web_process_memory_dump_test.cc',
       'weborigin/KnownPortsTest.cpp',
       'weborigin/KURLTest.cpp',
       'weborigin/OriginAccessEntryTest.cpp',
       'weborigin/SchemeRegistryTest.cpp',
       'weborigin/SecurityOriginTest.cpp',
       'weborigin/SecurityPolicyTest.cpp',
       'weborigin/SuboriginTest.cpp',
@@ skipping 87 matching lines @@
       ['use_default_render_theme==1',
         {
           'platform_test_files': [
             'scroll/ScrollbarThemeAuraTest.cpp',
           ],
         }
       ],
     ],
   },
 }