Log actions on the caller side

Some actions are exposed by the Device class, but logging success should
be done by the caller.

server/src/main/java/com/genymobile/scrcpy/Controller.java

@@ -110,11 +110,18 @@ public class Controller {
                 sender.pushClipboardText(clipboardText);
                 break;
             case ControlMessage.TYPE_SET_CLIPBOARD:
-                device.setClipboardText(msg.getText());
+                boolean setClipboardOk = device.setClipboardText(msg.getText());
+                if (setClipboardOk) {
+                    Ln.i("Device clipboard set");
+                }
                 break;
             case ControlMessage.TYPE_SET_SCREEN_POWER_MODE:
                 if (device.supportsInputEvents()) {
-                    device.setScreenPowerMode(msg.getAction());
+                    int mode = msg.getAction();
+                    boolean setPowerModeOk = device.setScreenPowerMode(mode);
+                    if (setPowerModeOk) {
+                        Ln.i("Device screen turned " + (mode == Device.POWER_MODE_OFF ? "off" : "on"));
+                    }
                 }
                 break;
             case ControlMessage.TYPE_ROTATE_DEVICE:

server/src/main/java/com/genymobile/scrcpy/Device.java

@@ -180,26 +180,20 @@ public final class Device {
         return s.toString();
     }
 
-    public void setClipboardText(String text) {
-        boolean ok = serviceManager.getClipboardManager().setText(text);
-        if (ok) {
-            Ln.i("Device clipboard set");
-        }
+    public boolean setClipboardText(String text) {
+        return serviceManager.getClipboardManager().setText(text);
     }
 
     /**
      * @param mode one of the {@code SCREEN_POWER_MODE_*} constants
      */
-    public void setScreenPowerMode(int mode) {
+    public boolean setScreenPowerMode(int mode) {
         IBinder d = SurfaceControl.getBuiltInDisplay();
         if (d == null) {
             Ln.e("Could not get built-in display");
-            return;
-        }
-        boolean ok = SurfaceControl.setDisplayPowerMode(d, mode);
-        if (ok) {
-            Ln.i("Device screen turned " + (mode == Device.POWER_MODE_OFF ? "off" : "on"));
+            return false;
         }
+        return SurfaceControl.setDisplayPowerMode(d, mode);
     }
 
     /**