Update Snackbar gesture inset calculation to factor in translationY

Fixes issue of compounding margins for legacy Snackbar which uses a slide animation that affects it's position on the screen

Resolves #741

PiperOrigin-RevId: 285246645
(cherry picked from commit 86b2ec3)

Author: dsn5ft

lib/java/com/google/android/material/snackbar/BaseTransientBottomBar.java

@@ -263,7 +263,10 @@ public boolean handleMessage(@NonNull Message message) {
       new Runnable() {
         @Override
         public void run() {
-          int currentInsetBottom = getScreenHeight() - getViewAbsoluteBottom();
+          // Calculate current bottom inset, factoring in translationY to account for where the
+          // view will likely be animating to.
+          int currentInsetBottom =
+              getScreenHeight() - getViewAbsoluteBottom() + (int) view.getTranslationY();
           if (currentInsetBottom >= extraBottomMarginGestureInset) {
             // No need to add extra offset if view is already outside of bottom gesture area
             return;