Add a --startup option to generate combined traces for startup.

tools/profile_chrome/main.py

Index: tools/profile_chrome/main.py
diff --git a/tools/profile_chrome/main.py b/tools/profile_chrome/main.py
index 1dbf08a60d9e98cf67ca6f21cebc369988aaf689..e493b9c83d61512ae7b5beda68d3c364a5954eec 100755
--- a/tools/profile_chrome/main.py
+++ b/tools/profile_chrome/main.py
@@ -11,6 +11,7 @@ import sys
 import webbrowser
 
 from profile_chrome import chrome_controller
+from profile_chrome import flags
 from profile_chrome import perf_controller
 from profile_chrome import profiler
 from profile_chrome import systrace_controller
@@ -119,15 +120,7 @@ def _CreateOptionParser():
                          action='store_true')
   parser.add_option_group(chrome_opts)
 
-  systrace_opts = optparse.OptionGroup(parser, 'Systrace tracing options')
-  systrace_opts.add_option('-s', '--systrace', help='Capture a systrace with '
-                        'the chosen comma-delimited systrace categories. You '
-                        'can also capture a combined Chrome + systrace by '
-                        'enable both types of categories. Use "list" to see '
-                        'the available categories. Systrace is disabled by '
-                        'default.', metavar='SYS_CATEGORIES',
-                        dest='systrace_categories', default='')
-  parser.add_option_group(systrace_opts)
+  parser.add_option_group(flags.SystraceOptions(parser))
 
   if perf_controller.PerfProfilerController.IsSupported():
     perf_opts = optparse.OptionGroup(parser, 'Perf profiling options')
@@ -139,13 +132,7 @@ def _CreateOptionParser():
                          metavar='PERF_CATEGORIES', dest='perf_categories')
     parser.add_option_group(perf_opts)
 
-  output_options = optparse.OptionGroup(parser, 'Output options')
-  output_options.add_option('-o', '--output', help='Save trace output to file.')
-  output_options.add_option('--json', help='Save trace as raw JSON instead of '
-                            'HTML.', action='store_true')
-  output_options.add_option('--view', help='Open resulting trace file in a '
-                            'browser.', action='store_true')
-  parser.add_option_group(output_options)
+  parser.add_option_group(flags.OutputOptions(parser))
 
   browsers = sorted(profiler.GetSupportedBrowsers().keys())
   parser.add_option('-b', '--browser', help='Select among installed browsers. '