[Android] Prevent keyboard accessory from cleaning cache early

Cleaning the cached password accessory right when the tab is closed was
too early: undo closing the tab would cause the cache to be unable to
restore the tab properly. Most visible impact: the key icon would be
gone temporarily.

This CL waits for committed tab closure (i.e. past the point of undoing)
to clear the cache.

Bug: 874798
Change-Id: I2dee7559e8c036f04dff2f2b0daf6c49c73ec8e5
Reviewed-on: https://chromium-review.googlesource.com/1185017Reviewed-by: Theresa <twellington@chromium.org>
Commit-Queue: Friedrich Horschig [CEST] <fhorschig@chromium.org>
Cr-Commit-Position: refs/heads/master@{#585433}

chrome/android/java/src/org/chromium/chrome/browser/autofill/keyboard_accessory/ManualFillingMediator.java

@@ -155,8 +155,13 @@ class ManualFillingMediator
             }
 
             @Override
-            public void willCloseTab(Tab tab, boolean animate) {
+            public void tabClosureCommitted(Tab tab) {
                 mModel.remove(tab);
+            }
+
+            @Override
+            public void willCloseTab(Tab tab, boolean animate) {
+                if (mActiveBrowserTab == tab) mActiveBrowserTab = null;
                 restoreCachedState(mActiveBrowserTab);
             }
         };

chrome/android/junit/src/org/chromium/chrome/browser/autofill/keyboard_accessory/ManualFillingControllerTest.java

@@ -261,6 +261,36 @@ public class ManualFillingControllerTest {
         assertThat(accessorySheetModel.getTabList().size(), is(0));
     }
 
+    @Test
+    public void testPasswordTabRestoredWhenClosingTabIsUndone() {
+        ManualFillingMediator mediator = mController.getMediatorForTesting();
+        KeyboardAccessoryModel keyboardAccessoryModel =
+                mediator.getKeyboardAccessory().getMediatorForTesting().getModelForTesting();
+        assertThat(keyboardAccessoryModel.getTabList().size(), is(0));
+
+        // Create a new tab with a passwords tab:
+        Tab tab = addTab(mediator, 1111, null);
+        mController.registerPasswordProvider(new PropertyProvider<>());
+        assertThat(keyboardAccessoryModel.getTabList().size(), is(1));
+
+        // Simulate closing the tab:
+        mediator.getTabModelObserverForTesting().willCloseTab(tab, false);
+        mediator.getTabObserverForTesting().onHidden(tab);
+        // Temporary removes the tab, but keeps it in memory so it can be brought back on undo:
+        assertThat(keyboardAccessoryModel.getTabList().size(), is(0));
+
+        // Simulate undo closing the tab and selecting it:
+        mediator.getTabModelObserverForTesting().tabClosureUndone(tab);
+        switchTab(mediator, null, tab);
+        // There should still be a tab in the accessory:
+        assertThat(keyboardAccessoryModel.getTabList().size(), is(1));
+
+        // Simulate closing the tab and committing to it (i.e. wait out undo message):
+        closeTab(mediator, tab, null);
+        mediator.getTabModelObserverForTesting().tabClosureCommitted(tab);
+        assertThat(keyboardAccessoryModel.getTabList().size(), is(0));
+    }
+
     @Test
     public void testRecoversFromInvalidState() {
         ManualFillingMediator mediator = mController.getMediatorForTesting();