[Predictive Back] Fixed possible NaN crashes in MaterialBottomContainerBackHelper, MaterialMainContainerBackHelper and MaterialSideContainerBackHelper.

There were some cases where we were dividing by the view's width and height in the  updateBackProgress methods, and this would cause a division by 0 exception and crash in cases where either the width or height are 0. Added a bunch of safeguards for division cases where the denominator could be 0.

PiperOrigin-RevId: 541929872

Author: afohrman

lib/java/com/google/android/material/motion/MaterialBottomContainerBackHelper.java

@@ -73,6 +73,10 @@ public void updateBackProgress(float progress) {
 
     float width = view.getWidth();
     float height = view.getHeight();
+    if (width <= 0f || height <= 0f) {
+      return;
+    }
+
     float maxScaleXDelta = maxScaleXDistance / width;
     float maxScaleYDelta = maxScaleYDistance / height;
     float scaleXDelta = AnimationUtils.lerp(0, maxScaleXDelta, progress);
@@ -89,7 +93,7 @@ public void updateBackProgress(float progress) {
         View childView = viewGroup.getChildAt(i);
         // Preserve the original aspect ratio and container alignment of the child content.
         childView.setPivotY(-childView.getTop());
-        childView.setScaleY(scaleX / scaleY);
+        childView.setScaleY(scaleY != 0f ? scaleX / scaleY : 1f);
       }
     }
   }

lib/java/com/google/android/material/motion/MaterialMainContainerBackHelper.java

@@ -115,6 +115,10 @@ public void updateBackProgress(
       float progress, boolean leftSwipeEdge, float touchY, float collapsedCornerSize) {
     float width = view.getWidth();
     float height = view.getHeight();
+    if (width <= 0f || height <= 0f) {
+      return;
+    }
+
     float scale = lerp(1, MIN_SCALE, progress);
 
     float availableHorizontalSpace = max(0, (width - MIN_SCALE * width) / 2 - minEdgeGap);

lib/java/com/google/android/material/motion/MaterialSideContainerBackHelper.java

@@ -87,6 +87,11 @@ public void updateBackProgress(float progress, boolean leftSwipeEdge, @GravityIn
 
     int width = view.getWidth();
     int height = view.getHeight();
+
+    if (width <= 0f || height <= 0f) {
+      return;
+    }
+
     float maxScaleXDeltaShrink = maxScaleXDistanceShrink / width;
     float maxScaleXDeltaGrow = maxScaleXDistanceGrow / width;
     float maxScaleYDelta = maxScaleYDistance / height;
@@ -112,7 +117,7 @@ public void updateBackProgress(float progress, boolean leftSwipeEdge, @GravityIn
                 : -childView.getLeft());
         childView.setPivotY(-childView.getTop());
         float childScaleX = swipeEdgeMatchesGravity ? 1 - scaleXDelta : 1f;
-        float childScaleY = scaleX / scaleY * childScaleX;
+        float childScaleY = scaleY != 0f ? scaleX / scaleY * childScaleX : 1f;
         childView.setScaleX(childScaleX);
         childView.setScaleY(childScaleY);
       }