[CD Taskbar] Cache displayId & Consolidate DisplayController methods

TaskbarActivityContext should store displayId and return a cached value to avoid unnessary binder calls.

Flag: com.android.window.flags.enable_taskbar_connected_displays
Bug: 406019031
Test: m
Change-Id: I808352e7098ee731abc7362b2f8f1b7a675457f9

quickstep/src/com/android/launcher3/taskbar/bubbles/BubbleBarView.java

@@ -44,7 +44,6 @@ import com.android.launcher3.R;
 import com.android.launcher3.anim.AnimatorListeners;
 import com.android.launcher3.taskbar.BarsLocationAnimatorHelper;
 import com.android.launcher3.taskbar.bubbles.animation.BubbleAnimator;
-import com.android.launcher3.util.DisplayController;
 import com.android.wm.shell.shared.bubbles.BubbleBarLocation;
 
 import java.io.PrintWriter;
@@ -656,7 +655,7 @@ public class BubbleBarView extends FrameLayout {
      * Get bubble bar top coordinate on screen when bar is resting
      */
     public int getRestingTopPositionOnScreen() {
-        int displayHeight = DisplayController.INSTANCE.get(getContext()).getInfo().currentSize.y;
+        int displayHeight = mController.getScreenHeight();
         int bubbleBarHeight = getBubbleBarBounds().height();
         return displayHeight - bubbleBarHeight + (int) mController.getBubbleBarTranslationY();
     }
@@ -1646,6 +1645,9 @@ public class BubbleBarView extends FrameLayout {
     /** Interface for BubbleBarView to communicate with its controller. */
     interface Controller {
 
+        /** Returns the screen height. */
+        int getScreenHeight();
+
         /** Returns the translation Y that the bubble bar should have. */
         float getBubbleBarTranslationY();