Add #hasCustomLifecycle() to BottomSheetContent.

This CL adds the concept of contents with custom lifecycle. This type of
content is not hidden nor cleared from the content queue when the user
navigates away from the current page or switches tab.

Bug: 933070
Change-Id: I092bff8a76bf119b2064a6a66a6e58b431486c5c
Reviewed-on: https://chromium-review.googlesource.com/c/1470228Reviewed-by: Theresa <twellington@chromium.org>
Reviewed-by: Matthew Jones <mdjones@chromium.org>
Commit-Queue: Jordan Demeulenaere <jdemeulenaere@chromium.org>
Cr-Commit-Position: refs/heads/master@{#635666}

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

@@ -321,6 +321,14 @@ public class BottomSheet
             return false;
         }
 
+        /**
+         * @return Whether this content owns its lifecycle. If false, the content will be hidden
+         *         when the user navigates away from the page or switches tab.
+         */
+        default boolean hasCustomLifecycle() {
+            return false;
+        }
+
         /**
          * @return The resource id of the content description for the bottom sheet. This is
          *         generally the name of the feature/content that is showing. 'Swipe down to close.'

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

@@ -26,6 +26,7 @@ import org.chromium.chrome.browser.widget.bottomsheet.BottomSheet.BottomSheetCon
 import org.chromium.chrome.browser.widget.bottomsheet.BottomSheet.StateChangeReason;
 
 import java.util.HashSet;
+import java.util.Iterator;
 import java.util.PriorityQueue;
 import java.util.Set;
 
@@ -140,7 +141,7 @@ public class BottomSheetController {
                     return;
                 }
 
-                // If refocusing the same tab, simply unsupress the sheet.
+                // If refocusing the same tab, simply unsuppress the sheet.
                 if (mLastActivityTab == tab) {
                     unsuppressSheet();
                     return;
@@ -375,17 +376,34 @@ public class BottomSheetController {
     }
 
     /**
-     * Clear all the content show requests and hide the current content.
+     * For all contents that don't have a custom lifecycle, we remove them from show requests or
+     * hide it if it is currently shown.
      */
     private void clearRequestsAndHide() {
-        mContentQueue.clear();
-        mFullShowRequestedSet.clear();
-        // TODO(mdjones): Replace usages of bottom sheet with a model in line with MVC.
-        // TODO(mdjones): It would probably be useful to expose an observer method that notifies
-        //                objects when all content requests are cleared.
-        hideContent(mBottomSheet.getCurrentSheetContent(), true);
-        mWasShownForCurrentTab = false;
-        mIsSuppressed = false;
+        clearRequests(mContentQueue.iterator());
+        clearRequests(mFullShowRequestedSet.iterator());
+
+        BottomSheetContent currentContent = mBottomSheet.getCurrentSheetContent();
+        if (currentContent != null && !currentContent.hasCustomLifecycle()) {
+            if (mContentQueue.isEmpty() && mFullShowRequestedSet.isEmpty()) {
+                mWasShownForCurrentTab = false;
+                mIsSuppressed = false;
+            }
+
+            hideContent(currentContent, /* animate= */ true);
+        }
+    }
+
+    /**
+     * Remove all contents from {@code iterator} that don't have a custom lifecycle.
+     * @param iterator The iterator whose items must be removed.
+     */
+    private void clearRequests(Iterator<BottomSheetContent> iterator) {
+        while (iterator.hasNext()) {
+            if (!iterator.next().hasCustomLifecycle()) {
+                iterator.remove();
+            }
+        }
     }
 
     /**

chrome/android/javatests/src/org/chromium/chrome/browser/widget/ScrimTest.java

@@ -123,7 +123,7 @@ public class ScrimTest {
 
         ThreadUtils.runOnUiThreadBlocking(() -> {
             mBottomSheet.showContent(new TestBottomSheetContent(
-                    mActivityTestRule.getActivity(), BottomSheet.ContentPriority.HIGH));
+                    mActivityTestRule.getActivity(), BottomSheet.ContentPriority.HIGH, false));
             mBottomSheet.setSheetState(BottomSheet.SheetState.HALF, false);
         });
 

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

@@ -24,6 +24,7 @@ import org.chromium.base.test.util.FlakyTest;
 import org.chromium.base.test.util.Restriction;
 import org.chromium.chrome.browser.ChromeSwitches;
 import org.chromium.chrome.browser.ChromeTabbedActivity;
+import org.chromium.chrome.browser.tab.EmptyTabObserver;
 import org.chromium.chrome.browser.tab.Tab;
 import org.chromium.chrome.browser.tabmodel.EmptyTabModelObserver;
 import org.chromium.chrome.browser.tabmodel.TabLaunchType;
@@ -77,9 +78,9 @@ public class BottomSheetControllerTest {
                     true);
 
             mLowPriorityContent = new TestBottomSheetContent(
-                    mActivityTestRule.getActivity(), ContentPriority.LOW);
+                    mActivityTestRule.getActivity(), ContentPriority.LOW, false);
             mHighPriorityContent = new TestBottomSheetContent(
-                    mActivityTestRule.getActivity(), ContentPriority.HIGH);
+                    mActivityTestRule.getActivity(), ContentPriority.HIGH, false);
         });
     }
 
@@ -225,6 +226,34 @@ public class BottomSheetControllerTest {
                 mBottomSheet.getCurrentSheetContent());
     }
 
+    @Test
+    @MediumTest
+    public void testCustomLifecycleContent() throws TimeoutException, InterruptedException {
+        requestContentInSheet(mHighPriorityContent, true);
+        requestContentInSheet(mLowPriorityContent, false);
+
+        TestBottomSheetContent customLifecycleContent = new TestBottomSheetContent(
+                mActivityTestRule.getActivity(), ContentPriority.LOW, true);
+        requestContentInSheet(customLifecycleContent, false);
+        assertEquals(mHighPriorityContent, mBottomSheet.getCurrentSheetContent());
+
+        // Change URL and wait for PageLoadStarted event.
+        CallbackHelper pageLoadStartedHelper = new CallbackHelper();
+        Tab tab = mActivityTestRule.getActivity().getActivityTab();
+        tab.addObserver(new EmptyTabObserver() {
+            @Override
+            public void onPageLoadStarted(Tab tab, String url) {
+                pageLoadStartedHelper.notifyCalled();
+            }
+        });
+        int currentCallCount = pageLoadStartedHelper.getCallCount();
+        ChromeTabUtils.loadUrlOnUiThread(tab, "about:blank");
+        pageLoadStartedHelper.waitForCallback(currentCallCount, 1);
+
+        ThreadUtils.runOnUiThreadBlocking(mBottomSheet::endAnimations);
+        assertEquals(customLifecycleContent, mBottomSheet.getCurrentSheetContent());
+    }
+
     /**
      * Request content be shown in the bottom sheet and end animations.
      * @param content The content to show.

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

@@ -40,7 +40,7 @@ public class BottomSheetObserverTest {
         mBottomSheetTestRule.startMainActivityOnBottomSheet(BottomSheet.SheetState.PEEK);
         ThreadUtils.runOnUiThreadBlocking(() -> {
             mBottomSheetTestRule.getBottomSheet().showContent(new TestBottomSheetContent(
-                    mBottomSheetTestRule.getActivity(), BottomSheet.ContentPriority.HIGH));
+                    mBottomSheetTestRule.getActivity(), BottomSheet.ContentPriority.HIGH, false));
         });
         mObserver = mBottomSheetTestRule.getObserver();
     }
@@ -223,7 +223,7 @@ public class BottomSheetObserverTest {
         int callCount = callbackHelper.getCallCount();
         ThreadUtils.runOnUiThreadBlocking(() -> {
             bottomSheet.showContent(new TestBottomSheetContent(
-                    mBottomSheetTestRule.getActivity(), BottomSheet.ContentPriority.HIGH) {
+                    mBottomSheetTestRule.getActivity(), BottomSheet.ContentPriority.HIGH, false) {
                 private final ViewGroup mContentView;
 
                 {

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

@@ -27,12 +27,18 @@ public class TestBottomSheetContent implements BottomSheetContent {
     /** This content's priority. */
     private @ContentPriority int mPriority;
 
+    /** Whether this content is browser specific. */
+    private boolean mHasCustomLifecycle;
+
     /**
      * @param context A context to inflate views with.
      * @param priority The content's priority.
+     * @param hasCustomLifecycle Whether the content is browser specific.
      */
-    public TestBottomSheetContent(Context context, @ContentPriority int priority) {
+    public TestBottomSheetContent(
+            Context context, @ContentPriority int priority, boolean hasCustomLifecycle) {
         mPriority = priority;
+        mHasCustomLifecycle = hasCustomLifecycle;
         ThreadUtils.runOnUiThreadBlocking(() -> {
             mToolbarView = new View(context);
             ViewGroup.LayoutParams params =
@@ -82,6 +88,11 @@ public class TestBottomSheetContent implements BottomSheetContent {
         return true;
     }
 
+    @Override
+    public boolean hasCustomLifecycle() {
+        return mHasCustomLifecycle;
+    }
+
     @Override
     public int getSheetContentDescriptionStringId() {
         return R.string.contextual_suggestions_button_description;