[cr tool] Fixing import problems

BUG=327999

Review URL: https://codereview.chromium.org/116363002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@243952 0039d316-1c4b-4281-b951-d872f2087c98

tools/cr/cr/actions/gdb.py

@@ -30,11 +30,10 @@ class GdbDebugger(cr.Debugger):
   def Attach(self, context, targets, arguments):
     raise NotImplementedError('Attach not currently supported for gdb.')
 
+  @classmethod
+  def ClassInit(cls):
+    # Attempt to find a valid gdb on the path.
+    gdb_binaries = cr.Host.SearchPath('gdb')
+    if gdb_binaries:
+      cls.DETECTED.Set(CR_GDB=gdb_binaries[0])
 
-def _DetectGdb():
-  """Attempts to find a valid gdb on the path."""
-  gdb_binaries = cr.Host.SearchPath('gdb')
-  if gdb_binaries:
-    GdbDebugger.DETECTED.Set(CR_GDB=gdb_binaries[0])
-
-_DetectGdb()

tools/cr/cr/actions/ninja.py

@@ -77,10 +77,8 @@ class NinjaBuilder(cr.Builder):
     return self._targets
 
   @classmethod
-  def DetectNinja(cls):
+  def ClassInit(cls):
     # TODO(iancottrell): If we can't detect ninja, we should be disabled.
     ninja_binaries = cr.Host.SearchPath('ninja')
     if ninja_binaries:
       cls.DETECTED.Set(NINJA_BINARY=ninja_binaries[0])
-
-NinjaBuilder.DetectNinja()

tools/cr/cr/commands/sync.py

@@ -44,12 +44,10 @@ class SyncCommand(cr.Command):
     cr.Host.Execute(context, '{GCLIENT_BINARY}', 'sync', *context.remains)
 
 
-def _AutoDetectGClient():
-  """Attempts to detect gclient and it's parent repository."""
-  gclient_binaries = cr.Host.SearchPath('gclient')
-  if gclient_binaries:
-    SyncCommand.DETECTED.Set(GCLIENT_BINARY=gclient_binaries[0])
-    SyncCommand.DETECTED.Set(DEPOT_TOOLS=os.path.dirname(gclient_binaries[0]))
-
-# Invoke the auto detection
-_AutoDetectGClient()
+  @classmethod
+  def ClassInit(cls):
+    # Attempt to detect gclient and it's parent repository.
+    gclient_binaries = cr.Host.SearchPath('gclient')
+    if gclient_binaries:
+      cls.DETECTED.Set(GCLIENT_BINARY=gclient_binaries[0])
+      cls.DETECTED.Set(DEPOT_TOOLS=os.path.dirname(gclient_binaries[0]))

tools/cr/cr/plugin.py

@@ -181,6 +181,10 @@ class Plugin(cr.loader.AutoExport):
       if config_root.only_active:
         getattr(self, config_root.property_name).enabled = False
 
+  @classmethod
+  def ClassInit(cls):
+    pass
+
   @classmethod
   def GetInstance(cls):
     """Gets an instance of this plugin.
@@ -193,6 +197,8 @@ class Plugin(cr.loader.AutoExport):
     """
     plugin = _plugins.get(cls, None)
     if plugin is None:
+      # Run delayed class initialization
+      cls.ClassInit()
       # Build a new instance of cls, and register it as the main instance.
       plugin = cls()
       _plugins[cls] = plugin