Do not log success on failure

If calling the private API does not work, an exception is printed. In
that case, do not log that the action succeeded.

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

@@ -163,9 +163,11 @@ public final class Device {
     }
 
     public void setClipboardText(String text) {
-        serviceManager.getClipboardManager().setText(text);
+        boolean ok = serviceManager.getClipboardManager().setText(text);
+        if (ok) {
             Ln.i("Device clipboard set");
         }
+    }
 
     /**
      * @param mode one of the {@code SCREEN_POWER_MODE_*} constants
@@ -176,9 +178,11 @@ public final class Device {
             Ln.e("Could not get built-in display");
             return;
         }
-        SurfaceControl.setDisplayPowerMode(d, mode);
+        boolean ok = SurfaceControl.setDisplayPowerMode(d, mode);
+        if (ok) {
             Ln.i("Device screen turned " + (mode == Device.POWER_MODE_OFF ? "off" : "on"));
         }
+    }
 
     /**
      * Disable auto-rotation (if enabled), set the screen rotation and re-enable auto-rotation (if it was enabled).

server/src/main/java/com/genymobile/scrcpy/wrappers/ClipboardManager.java

@@ -74,13 +74,15 @@ public class ClipboardManager {
         }
     }
 
-    public void setText(CharSequence text) {
+    public boolean setText(CharSequence text) {
         try {
             Method method = getSetPrimaryClipMethod();
             ClipData clipData = ClipData.newPlainText(null, text);
             setPrimaryClip(method, manager, clipData);
+            return true;
         } catch (InvocationTargetException | IllegalAccessException | NoSuchMethodException e) {
             Ln.e("Could not invoke method", e);
+            return false;
         }
     }
 }

server/src/main/java/com/genymobile/scrcpy/wrappers/SurfaceControl.java

@@ -121,12 +121,14 @@ public final class SurfaceControl {
         return setDisplayPowerModeMethod;
     }
 
-    public static void setDisplayPowerMode(IBinder displayToken, int mode) {
+    public static boolean setDisplayPowerMode(IBinder displayToken, int mode) {
         try {
             Method method = getSetDisplayPowerModeMethod();
             method.invoke(null, displayToken, mode);
+            return true;
         } catch (InvocationTargetException | IllegalAccessException | NoSuchMethodException e) {
             Ln.e("Could not invoke method", e);
+            return false;
         }
     }