DevTools: always use 16bit strings for inspector protocol.

third_party/WebKit/Source/platform/blink_platform.gypi

 {
   'includes': [
     'platform_generated.gypi',
   ],
   'variables': {
     'platform_files': [
       'AsyncFileSystemCallbacks.h',
       'CalculationValue.h',
       'CheckedInt.h',
       'ContentDecryptionModuleResult.h',
@@ skipping 814 matching lines @@
       'inspector_protocol/Array.h',
       'inspector_protocol/Collections.h',
       'inspector_protocol/CollectionsWTF.h',
       'inspector_protocol/ErrorSupport.cpp',
       'inspector_protocol/ErrorSupport.h',
       'inspector_protocol/Maybe.h',
       'inspector_protocol/Parser.cpp',
       'inspector_protocol/Parser.h',
       'inspector_protocol/FrontendChannel.h',
       'inspector_protocol/String16.h',
+      'inspector_protocol/String16WTF.cpp',
       'inspector_protocol/String16WTF.h',
       'inspector_protocol/Values.cpp',
       'inspector_protocol/Values.h',
       'inspector_protocol/ValueConversions.cpp',
       'inspector_protocol/ValueConversions.h',
       'mac/BlockExceptions.h',
       'mac/BlockExceptions.mm',
       'mac/ColorMac.h',
       'mac/ColorMac.mm',
       'mac/KillRingMac.mm',
@@ skipping 432 matching lines @@
       ['OS!="mac"',
         {
           'platform_test_files': [
             'scroll/ScrollAnimatorTest.cpp',
           ],
         }
       ],
     ],
   },
 }