Effect: Remove unnecessary "this" qualifier

`transformationMatrix` is not ambiguous, as there's no other local
transformationMatrix variable nearby.

PiperOrigin-RevId: 482184602
(cherry picked from commit c698ec51)

library/effect/src/main/java/com/google/android/exoplayer2/effect/ScaleToFitTransformation.java

@@ -97,9 +97,9 @@ public final class ScaleToFitTransformation implements MatrixTransformation {
    * @param rotationDegrees How much to rotate the frame counterclockwise, in degrees.
    */
   private ScaleToFitTransformation(float scaleX, float scaleY, float rotationDegrees) {
-    this.transformationMatrix = new Matrix();
-    this.transformationMatrix.postScale(scaleX, scaleY);
-    this.transformationMatrix.postRotate(rotationDegrees);
+    transformationMatrix = new Matrix();
+    transformationMatrix.postScale(scaleX, scaleY);
+    transformationMatrix.postRotate(rotationDegrees);
   }
 
   @Override