bluetooth: Enable BluetoothAdapterFactory on android.

BUG=471536

Review URL: https://codereview.chromium.org/1130783004

Cr-Commit-Position: refs/heads/master@{#329755}

device/bluetooth/bluetooth_adapter_android.cc

@@ -68,8 +68,7 @@ void BluetoothAdapterAndroid::SetName(const std::string& name,
 }
 
 bool BluetoothAdapterAndroid::IsInitialized() const {
-  NOTIMPLEMENTED();
-  return false;
+  return true;
 }
 
 bool BluetoothAdapterAndroid::IsPresent() const {
@@ -147,18 +146,21 @@ void BluetoothAdapterAndroid::AddDiscoverySession(
     BluetoothDiscoveryFilter* discovery_filter,
     const base::Closure& callback,
     const ErrorCallback& error_callback) {
+  error_callback.Run();
 }
 
 void BluetoothAdapterAndroid::RemoveDiscoverySession(
     BluetoothDiscoveryFilter* discovery_filter,
     const base::Closure& callback,
     const ErrorCallback& error_callback) {
+  error_callback.Run();
 }
 
 void BluetoothAdapterAndroid::SetDiscoveryFilter(
     scoped_ptr<BluetoothDiscoveryFilter> discovery_filter,
     const base::Closure& callback,
     const ErrorCallback& error_callback) {
+  error_callback.Run();
 }
 
 void BluetoothAdapterAndroid::RemovePairingDelegateInternal(

device/bluetooth/bluetooth_adapter_factory.cc

@@ -62,7 +62,7 @@ bool BluetoothAdapterFactory::IsBluetoothAdapterAvailable() {
   // instance even on platforms that would otherwise not support it.
   if (default_adapter.Get())
     return true;
-#if defined(OS_CHROMEOS) || defined(OS_WIN)
+#if defined(OS_ANDROID) || defined(OS_CHROMEOS) || defined(OS_WIN)
   return true;
 #elif defined(OS_MACOSX)
   return base::mac::IsOSLionOrLater();