Fix fake_specs.py, update recipe expectation

infra/bots/recipes/swarm_compile.expected/Build-Ubuntu-Clang-x86_64-Debug-GN.json

 [
   {
     "cmd": [
       "python",
       "-u",
       "\nimport sys, os\npath = sys.argv[1]\nmode = int(sys.argv[2])\nif not os.path.isdir(path):\n  if os.path.exists(path):\n    print \"%s exists but is not a dir\" % path\n    sys.exit(1)\n  os.makedirs(path, mode)\n",
       "[CUSTOM_/_B_WORK]",
       "511"
     ],
     "name": "makedirs checkout_path",
@@ skipping 83 matching lines @@
       "@@@STEP_LOG_LINE@json.output@    \"role\": \"Build\", @@@",
       "@@@STEP_LOG_LINE@json.output@    \"target_arch\": \"x86_64\"@@@",
       "@@@STEP_LOG_LINE@json.output@  }, @@@",
       "@@@STEP_LOG_LINE@json.output@  \"configuration\": \"Debug\", @@@",
       "@@@STEP_LOG_LINE@json.output@  \"dm_flags\": [@@@",
       "@@@STEP_LOG_LINE@json.output@    \"--dummy-flags\"@@@",
       "@@@STEP_LOG_LINE@json.output@  ], @@@",
       "@@@STEP_LOG_LINE@json.output@  \"do_perf_steps\": false, @@@",
       "@@@STEP_LOG_LINE@json.output@  \"do_test_steps\": false, @@@",
       "@@@STEP_LOG_LINE@json.output@  \"env\": {@@@",
-      "@@@STEP_LOG_LINE@json.output@    \"GYP_DEFINES\": \"skia_arch_type=x86_64 skia_warnings_as_errors=1\"@@@",
+      "@@@STEP_LOG_LINE@json.output@    \"CC\": \"/usr/bin/clang\", @@@",
+      "@@@STEP_LOG_LINE@json.output@    \"CXX\": \"/usr/bin/clang++\", @@@",
+      "@@@STEP_LOG_LINE@json.output@    \"GYP_DEFINES\": \"skia_arch_type=x86_64 skia_clang_build=1 skia_warnings_as_errors=1\"@@@",
       "@@@STEP_LOG_LINE@json.output@  }, @@@",
       "@@@STEP_LOG_LINE@json.output@  \"nanobench_flags\": [@@@",
       "@@@STEP_LOG_LINE@json.output@    \"--dummy-flags\"@@@",
       "@@@STEP_LOG_LINE@json.output@  ], @@@",
       "@@@STEP_LOG_LINE@json.output@  \"upload_dm_results\": true, @@@",
       "@@@STEP_LOG_LINE@json.output@  \"upload_perf_results\": false@@@",
       "@@@STEP_LOG_LINE@json.output@}@@@",
       "@@@STEP_LOG_END@json.output@@@"
     ]
   },
   {
     "cmd": [
       "[CUSTOM_/_B_WORK]/skia/bin/fetch-gn"
     ],
     "cwd": "[CUSTOM_/_B_WORK]/skia",
     "env": {
       "BUILDTYPE": "Debug",
+      "CC": "/usr/bin/clang",
       "CHROME_HEADLESS": "1",
-      "GYP_DEFINES": "skia_arch_type=x86_64 skia_warnings_as_errors=1",
+      "CXX": "/usr/bin/clang++",
+      "GYP_DEFINES": "skia_arch_type=x86_64 skia_clang_build=1 skia_warnings_as_errors=1",
       "PATH": "%(PATH)s:RECIPE_PACKAGE_REPO[depot_tools]:RECIPE_PACKAGE_REPO[depot_tools]",
       "SKIA_OUT": "[CUSTOM_/_B_WORK]/skia/out/Build-Ubuntu-Clang-x86_64-Debug-GN"
     },
     "name": "fetch-gn"
   },
   {
     "cmd": [
       "python",
       "-u",
       "import json\nimport subprocess\nimport sys\n\nccache = None\ntry:\n  ccache = subprocess.check_output(['which', 'ccache']).rstrip()\nexcept:\n  pass\nprint json.dumps({'ccache': ccache})\n"
     ],
     "env": {
       "BUILDTYPE": "Debug",
+      "CC": "/usr/bin/clang",
       "CHROME_HEADLESS": "1",
-      "GYP_DEFINES": "skia_arch_type=x86_64 skia_warnings_as_errors=1",
+      "CXX": "/usr/bin/clang++",
+      "GYP_DEFINES": "skia_arch_type=x86_64 skia_clang_build=1 skia_warnings_as_errors=1",
       "PATH": "%(PATH)s:RECIPE_PACKAGE_REPO[depot_tools]:RECIPE_PACKAGE_REPO[depot_tools]",
       "SKIA_OUT": "[CUSTOM_/_B_WORK]/skia/out/Build-Ubuntu-Clang-x86_64-Debug-GN"
     },
     "name": "has ccache?",
     "stdout": "/path/to/tmp/json",
     "~followup_annotations": [
       "@@@STEP_LOG_LINE@json.output@{@@@",
       "@@@STEP_LOG_LINE@json.output@  \"ccache\": \"/usr/bin/ccache\"@@@",
       "@@@STEP_LOG_LINE@json.output@}@@@",
       "@@@STEP_LOG_END@json.output@@@",
@@ skipping 13 matching lines @@
   {
     "cmd": [
       "gn",
       "gen",
       "[CUSTOM_/_B_WORK]/skia/out/Build-Ubuntu-Clang-x86_64-Debug-GN/Debug",
       "--args=is_debug=true cc=\"/usr/bin/ccache clang -Qunused-arguments\" cxx=\"/usr/bin/ccache clang++ -Qunused-arguments\""
     ],
     "cwd": "[CUSTOM_/_B_WORK]/skia",
     "env": {
       "BUILDTYPE": "Debug",
+      "CC": "/usr/bin/clang",
       "CHROME_HEADLESS": "1",
-      "GYP_DEFINES": "skia_arch_type=x86_64 skia_warnings_as_errors=1",
+      "CXX": "/usr/bin/clang++",
+      "GYP_DEFINES": "skia_arch_type=x86_64 skia_clang_build=1 skia_warnings_as_errors=1",
       "PATH": "%(PATH)s:RECIPE_PACKAGE_REPO[depot_tools]:RECIPE_PACKAGE_REPO[depot_tools]",
       "SKIA_OUT": "[CUSTOM_/_B_WORK]/skia/out/Build-Ubuntu-Clang-x86_64-Debug-GN"
     },
     "name": "gn_gen"
   },
   {
     "cmd": [
       "ninja",
       "-C",
       "[CUSTOM_/_B_WORK]/skia/out/Build-Ubuntu-Clang-x86_64-Debug-GN/Debug"
     ],
     "cwd": "[CUSTOM_/_B_WORK]/skia",
     "env": {
       "BUILDTYPE": "Debug",
+      "CC": "/usr/bin/clang",
       "CHROME_HEADLESS": "1",
-      "GYP_DEFINES": "skia_arch_type=x86_64 skia_warnings_as_errors=1",
+      "CXX": "/usr/bin/clang++",
+      "GYP_DEFINES": "skia_arch_type=x86_64 skia_clang_build=1 skia_warnings_as_errors=1",
       "PATH": "%(PATH)s:RECIPE_PACKAGE_REPO[depot_tools]:RECIPE_PACKAGE_REPO[depot_tools]",
       "SKIA_OUT": "[CUSTOM_/_B_WORK]/skia/out/Build-Ubuntu-Clang-x86_64-Debug-GN"
     },
     "name": "compile most"
   },
   {
     "cmd": [
       "python",
       "-u",
       "import errno\nimport glob\nimport os\nimport shutil\nimport sys\n\nsrc = sys.argv[1]\ndst = sys.argv[2]\nbuild_products_whitelist = ['dm', 'dm.exe', 'nanobench', 'nanobench.exe', '*.so', '*.dll', '*.dylib', 'skia_launcher', 'lib/*.so', 'iOSShell.app', 'iOSShell.ipa', 'visualbench', 'visualbench.exe', 'vulkan-1.dll']\n\ntry:\n  os.makedirs(dst)\nexcept OSError as e:\n  if e.errno != errno.EEXIST:\n    raise\n\nfor pattern in build_products_whitelist:\n  path = os.path.join(src, pattern)\n  for f in glob.glob(path):\n    dst_path = os.path.join(dst, os.path.relpath(f, src))\n    if not os.path.isdir(os.path.dirname(dst_path)):\n      os.makedirs(os.path.dirname(dst_path))\n    print 'Copying build product %s to %s' % (f, dst_path)\n    shutil.move(f, dst_path)\n",
@@ skipping 28 matching lines @@
       "@@@STEP_LOG_LINE@python.inline@    shutil.move(f, dst_path)@@@",
       "@@@STEP_LOG_END@python.inline@@@"
     ]
   },
   {
     "name": "$result",
     "recipe_result": null,
     "status_code": 0
   }
 ]