Revert of Move remote platforms creation logic from android_browser_finder to platform

tools/telemetry/telemetry/core/platform/platform_backend.py

Index: tools/telemetry/telemetry/core/platform/platform_backend.py
diff --git a/tools/telemetry/telemetry/core/platform/platform_backend.py b/tools/telemetry/telemetry/core/platform/platform_backend.py
index 2b9ce567cff586adb84ab33b0579b916d231f1d8..710b8e596d45cffa86725b5d2f5496ca53cf3600 100644
--- a/tools/telemetry/telemetry/core/platform/platform_backend.py
+++ b/tools/telemetry/telemetry/core/platform/platform_backend.py
@@ -44,31 +44,13 @@
 
 
 class PlatformBackend(object):
-
-  def __init__(self, device=None):
-    """ Initalize an instance of PlatformBackend from a device optionally.
-      Call sites need to use SupportsDevice before intialization to check
-      whether this platform backend supports the device.
-      If device is None, this constructor returns the host platform backend
-      which telemetry is running on.
-
-      Args:
-        device: an instance of telemetry.core.platform.device.Device.
-    """
-    if device and not self.SupportsDevice(device):
-      raise ValueError('Unsupported device: %s' % device.name)
+  def __init__(self):
     self._platform = None
     self._running_browser_backends = weakref.WeakSet()
     self._tracing_controller_backend = (
         tracing_controller_backend.TracingControllerBackend(self))
     self._profiling_controller_backend = (
         profiling_controller_backend.ProfilingControllerBackend(self))
-
-  @classmethod
-  def SupportsDevice(cls, device):
-    """ Returns whether this platform backend supports intialization from the
-    device. """
-    return False
 
   def SetPlatform(self, platform):
     assert self._platform == None