shill: implement manager.RequestScan (for WiFi only)

BUG=chromium-os:19831
TEST=unittests, WiFiManager/000_SSID_Length_Limit

note that 000_SSID_Length_Limit does not pass yet,
because we don't do IP configuration yet. but it
does get scan results.

Change-Id: I8993b3c646eda705271d1f7ad7d7341c692ae06b
Reviewed-on: http://gerrit.chromium.org/gerrit/7407
Reviewed-by: mukesh agrawal <quiche@chromium.org>
Tested-by: mukesh agrawal <quiche@chromium.org>
diff --git a/mock_adaptors.h b/mock_adaptors.h
index 4f3b2e6..30b0901 100644
--- a/mock_adaptors.h
+++ b/mock_adaptors.h
@@ -67,6 +67,8 @@
   MOCK_METHOD2(EmitUintChanged, void(const std::string&, uint32));
   MOCK_METHOD2(EmitIntChanged, void(const std::string&, int));
   MOCK_METHOD2(EmitStringChanged, void(const std::string&, const std::string&));
+  MOCK_METHOD2(EmitRpcIdentifierArrayChanged,
+               void(const std::string &, const std::vector<std::string> &));
 
   MOCK_METHOD1(EmitStateChanged, void(const std::string&));