Add shell::Tracer object and wire up to --trace-startup on Android

PRESUBMIT.py

 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """Top-level presubmit script for Chromium.
 
 See http://dev.chromium.org/developers/how-tos/depottools/presubmit-scripts
 for more details about the presubmit API built into gcl.
 """
 
@@ skipping 622 matching lines @@
   return results
 
 
 def _CheckSpamLogging(input_api, output_api):
   file_inclusion_pattern = r'.+%s' % _IMPLEMENTATION_EXTENSIONS
   black_list = (_EXCLUDED_PATHS +
                 _TEST_CODE_EXCLUDED_PATHS +
                 input_api.DEFAULT_BLACK_LIST +
                 (r"^base/logging\.h$",
                  r"^base/logging\.cc$",
-                 r"^shell/native_application_loader\.cc$",
+                 r"^shell/application_manager/network_fetcher\.cc$",
+                 r"^shell/tracer\.cc$",
                  r"^sandbox/linux/.*",
-                 r"^tools/",))
+                 r"^tools/.*"))
   source_file_filter = lambda x: input_api.FilterSourceFile(
       x, white_list=(file_inclusion_pattern,), black_list=black_list)
 
   log_macro = input_api.re.compile(r"\bD?LOG\s*\(\s*INFO\s*\)")
   log_if_macro = input_api.re.compile(r"\bD?LOG_IF\s*\(\s*INFO\s*,")
   printf_macro = input_api.re.compile(r"\bprintf\(")
   fprintf_macro = input_api.re.compile(r"\bfprintf\((stdout|stderr)")
 
   log_info = []
   printf = []
@@ skipping 483 matching lines @@
       'Mojo ChromeOS Builder (dbg) Try',
       'Mojo ChromeOS Builder Try',
       'Mojo Linux (dbg) Try',
       'Mojo Linux ASan Try',
       'Mojo Linux NaCl (dbg) Try',
       'Mojo Linux NaCl Try',
       'Mojo Linux Try',
   ]
 
   return GetDefaultTryConfigs(builders)