Add test for GTS bottom padding

Bug: 997250
Change-Id: I929aed84f8a7bee7371506a731dd453d10597662
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2490032
Commit-Queue: Zhiyuan Cai <zhiyuancai@google.com>
Reviewed-by: Yue Zhang <yuezhanggg@chromium.org>
Reviewed-by: Wei-Yin Chen (陳威尹) <wychen@chromium.org>
Cr-Commit-Position: refs/heads/master@{#823994}

chrome/android/features/tab_ui/javatests/src/org/chromium/chrome/browser/tasks/tab_management/TabListContainerViewBinderTest.java

@@ -279,6 +279,16 @@ public class TabListContainerViewBinderTest extends DummyUiActivityTestCase {
                 INCREASED_CONTAINER_HEIGHT, shadowImageView.getTranslationY(), MathUtils.EPSILON);
     }
 
+    @Test
+    @MediumTest
+    @UiThreadTest
+    public void testBottomPaddingSetsBottomPadding() {
+        assertThat(mRecyclerView.getPaddingBottom(), equalTo(0));
+
+        mContainerModel.set(TabListContainerProperties.BOTTOM_PADDING, CONTAINER_HEIGHT);
+        assertThat(mRecyclerView.getPaddingBottom(), equalTo(CONTAINER_HEIGHT));
+    }
+
     @Override
     public void tearDownTest() throws Exception {
         mMCP.destroy();

chrome/android/features/tab_ui/junit/src/org/chromium/chrome/browser/tasks/tab_management/TabSwitcherMediatorUnitTest.java

@@ -57,6 +57,7 @@ import org.chromium.chrome.browser.tabmodel.TabModelFilterProvider;
 import org.chromium.chrome.browser.tabmodel.TabModelObserver;
 import org.chromium.chrome.browser.tabmodel.TabModelSelectorImpl;
 import org.chromium.chrome.browser.tabmodel.TabModelSelectorObserver;
+import org.chromium.chrome.tab_ui.R;
 import org.chromium.chrome.test.util.browser.Features;
 import org.chromium.chrome.test.util.browser.Features.DisableFeatures;
 import org.chromium.chrome.test.util.browser.Features.EnableFeatures;
@@ -784,6 +785,23 @@ public class TabSwitcherMediatorUnitTest {
         assertEquals(0, mModel.get(TabListContainerProperties.SHADOW_TOP_OFFSET));
     }
 
+    @Test
+    public void updatesBottomPaddingOnlyInGridMode() {
+        doReturn(16f).when(mResources).getDimension(R.dimen.tab_grid_bottom_padding);
+
+        assertEquals(0, mModel.get(TabListContainerProperties.BOTTOM_PADDING));
+        new TabSwitcherMediator(mContext, mResetHandler, mModel, mTabModelSelector,
+                mBrowserControlsStateProvider, mCompositorViewHolder, null, mMessageItemsController,
+                mMultiWindowModeStateDispatcher, TabListCoordinator.TabListMode.GRID);
+        assertEquals(16, mModel.get(TabListContainerProperties.BOTTOM_PADDING));
+
+        mModel.set(TabListContainerProperties.BOTTOM_PADDING, 0);
+        new TabSwitcherMediator(mContext, mResetHandler, mModel, mTabModelSelector,
+                mBrowserControlsStateProvider, mCompositorViewHolder, null, mMessageItemsController,
+                mMultiWindowModeStateDispatcher, TabListCoordinator.TabListMode.STRIP);
+        assertEquals(0, mModel.get(TabListContainerProperties.BOTTOM_PADDING));
+    }
+
     @Test
     public void enterMultiWindowMode() {
         initAndAssertAllProperties();