Add the /profile flag to linker options for official builds.

build/internal/release_impl_official.gypi

 {
   'includes': ['release_defaults.gypi'],
   'defines': ['OFFICIAL_BUILD'],
   'msvs_settings': {
     'VCCLCompilerTool': {
       'Optimization': '3',
       'InlineFunctionExpansion': '2',
       'EnableIntrinsicFunctions': 'true',
       'FavorSizeOrSpeed': '2',
       'OmitFramePointers': 'true',
       'EnableFiberSafeOptimizations': 'true',
       'WholeProgramOptimization': 'true',
     },
     'VCLibrarianTool': {
       'AdditionalOptions': ['/ltcg', '/expectedoutputsize:120000000'],
     },
     'VCLinkerTool': {
       'LinkTimeCodeGeneration': '1',
+      # The /PROFILE flag causes the linker to add a "FIXUP" debug stream to
+      # the generated PDB. According to MSDN documentation, this flag is only
+      # available (or perhaps supported) in the Enterprise (team development)
+      # version of Visual Studio. If this blocks your official build, simply
+      # comment out this line, then  re-run "gclient runhooks".
+      'Profile': 'true',
     },
   },
 }