Make sure to call BottomSheetContent#destroy

This patch calls the previously manually called destroy method on
BottomSheetContent. This is triggered when the sheet is hidden (and
not suppressed), regardless of whether the sheet has a custom
lifecycle.

Change-Id: I392fd98e384cfbdc73422959417e20b246da2f3e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1879688Reviewed-by: Theresa  <twellington@chromium.org>
Commit-Queue: Matthew Jones <mdjones@chromium.org>
Cr-Commit-Position: refs/heads/master@{#709918}

chrome/android/java/src/org/chromium/chrome/browser/widget/bottomsheet/BottomSheet.java

@@ -279,7 +279,11 @@ public class BottomSheet
         int getVerticalScrollOffset();
 
         /**
-         * Called to destroy the {@link BottomSheetContent} when it is no longer in use.
+         * Called to destroy the {@link BottomSheetContent} when it is dismissed. The means the
+         * sheet is in the {@link SheetState#HIDDEN} state without being suppressed. This method
+         * does not necessarily need to be used but exists for convenience. Cleanup can be done
+         * manually via the owning component (likely watching for the sheet hidden event using an
+         * observer).
          */
         void destroy();
 

chrome/android/java/src/org/chromium/chrome/browser/widget/bottomsheet/BottomSheetController.java

@@ -189,6 +189,9 @@ public class BottomSheetController implements Destroyable {
             @Override
             public void onSheetStateChanged(@SheetState int state) {
                 if (state != SheetState.HIDDEN || mIsSuppressed) return;
+                if (mBottomSheet.getCurrentSheetContent() != null) {
+                    mBottomSheet.getCurrentSheetContent().destroy();
+                }
                 mIsProcessingHideRequest = false;
                 showNextContent(true);
             }

chrome/android/javatests/src/org/chromium/chrome/browser/widget/bottomsheet/BottomSheetControllerTest.java

@@ -210,6 +210,24 @@ public class BottomSheetControllerTest {
                 mBottomSheet.getCurrentSheetContent());
     }
 
+    @Test
+    @MediumTest
+    @Feature({"BottomSheetController"})
+    public void testContentDestroyedOnHidden() throws TimeoutException {
+        requestContentInSheet(mLowPriorityContent, true);
+        int destroyCallCount = mLowPriorityContent.destroyCallbackHelper.getCallCount();
+
+        // Enter the tab switcher and select a different tab.
+        ThreadUtils.runOnUiThreadBlocking(
+                () -> { mBottomSheet.setSheetState(BottomSheet.SheetState.HIDDEN, false); });
+
+        mLowPriorityContent.destroyCallbackHelper.waitForCallback(destroyCallCount);
+        assertEquals("The bottom sheet should be hidden.", BottomSheet.SheetState.HIDDEN,
+                mBottomSheet.getSheetState());
+        assertEquals("The bottom sheet is showing incorrect content.", null,
+                mBottomSheet.getCurrentSheetContent());
+    }
+
     @Test
     @MediumTest
     @Feature({"BottomSheetController"})

chrome/android/javatests/src/org/chromium/chrome/browser/widget/bottomsheet/TestBottomSheetContent.java

@@ -12,12 +12,16 @@ import android.view.ViewGroup;
 
 import androidx.annotation.Nullable;
 
+import org.chromium.base.test.util.CallbackHelper;
 import org.chromium.chrome.browser.widget.bottomsheet.BottomSheet.BottomSheetContent;
 import org.chromium.chrome.browser.widget.bottomsheet.BottomSheet.ContentPriority;
 import org.chromium.content_public.browser.test.util.TestThreadUtils;
 
 /** A simple sheet content to test with. This only displays two empty white views. */
 public class TestBottomSheetContent implements BottomSheetContent {
+    /** {@link CallbackHelper} to ensure the destroy method is called. */
+    public final CallbackHelper destroyCallbackHelper = new CallbackHelper();
+
     /** Empty view that represents the toolbar. */
     private View mToolbarView;
 
@@ -82,7 +86,9 @@ public class TestBottomSheetContent implements BottomSheetContent {
     }
 
     @Override
-    public void destroy() {}
+    public void destroy() {
+        destroyCallbackHelper.notifyCalled();
+    }
 
     @Override
     public int getPriority() {