ARC: Implement SetWifiEnabledState API.

components/arc/common/net.mojom

Index: components/arc/common/net.mojom
diff --git a/components/arc/common/net.mojom b/components/arc/common/net.mojom
index 67c3abee6a6952d4e817102f2da5d3f2da8964ed..408d5055c12eb2c4fbb4577455973fc6956d3825 100644
--- a/components/arc/common/net.mojom
+++ b/components/arc/common/net.mojom
@@ -47,6 +47,12 @@ interface NetHost {
   // Sends a request to get configured or visible WiFi networks based on the
   // request type.
   [MinVersion=2] GetNetworks@3(GetNetworksRequestType type) => (NetworkData data);
+
+  // Sends a request to enable or disable WiFi. The |result| is true when the
+  // the state has been successfully set or WiFi is already in the desired

[hidehiko, 2016/03/16 01:47:56]

How about mentioning about that the setting can fail in later phase, but the
error will be simply ignored.

+  // state. It is false if WiFi manipulation is prohibited due to a policy or its

[hidehiko, 2016/03/16 01:47:56]

nit: wrap line.

+  // current state.
+  [MinVersion=3] SetWifiEnabledState@4(bool is_enabled) => (bool result);
 };
 
 interface NetInstance {