Reland of Disable swipe down to enter the tab switcher in Chrome Home.

chrome/android/java/src/org/chromium/chrome/browser/compositor/layouts/LayoutManagerChromePhone.java

Index: chrome/android/java/src/org/chromium/chrome/browser/compositor/layouts/LayoutManagerChromePhone.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/compositor/layouts/LayoutManagerChromePhone.java b/chrome/android/java/src/org/chromium/chrome/browser/compositor/layouts/LayoutManagerChromePhone.java
index aaa12a028fb4eed46f509b1aa6b5992d3da7e7da..9e12b097ad6249b2940ef6254272a308253b73e9 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/compositor/layouts/LayoutManagerChromePhone.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/compositor/layouts/LayoutManagerChromePhone.java
@@ -8,6 +8,7 @@
 import android.view.ViewGroup;
 
 import org.chromium.chrome.browser.compositor.layouts.content.TabContentManager;
+import org.chromium.chrome.browser.compositor.layouts.eventfilter.EdgeSwipeEventFilter.ScrollDirection;
 import org.chromium.chrome.browser.compositor.layouts.phone.SimpleAnimationLayout;
 import org.chromium.chrome.browser.compositor.overlays.SceneOverlay;
 import org.chromium.chrome.browser.contextualsearch.ContextualSearchManagementDelegate;
@@ -17,6 +18,7 @@
 import org.chromium.chrome.browser.tabmodel.TabModel.TabLaunchType;
 import org.chromium.chrome.browser.tabmodel.TabModelSelector;
 import org.chromium.chrome.browser.tabmodel.TabModelUtils;
+import org.chromium.chrome.browser.util.FeatureUtilities;
 import org.chromium.ui.resources.dynamics.DynamicResourceLoader;
 
 /**
@@ -45,6 +47,11 @@
         // Set up layout parameters
         mStaticLayout.setLayoutHandlesTabLifecycles(false);
         mToolbarSwipeLayout.setMovesToolbar(true);
+    }
+
+    @Override
+    protected ToolbarSwipeHandler createToolbarSwipeHandler(LayoutProvider provider) {
+        return new PhoneToolbarSwipeHandler(provider);
     }
 
     @Override
@@ -150,4 +157,19 @@
         mTitleCache.remove(id);
         super.releaseTabLayout(id);
     }
+
+    private class PhoneToolbarSwipeHandler extends ToolbarSwipeHandler {
+        public PhoneToolbarSwipeHandler(LayoutProvider provider) {
+            super(provider);
+        }
+
+        @Override
+        public boolean isSwipeEnabled(ScrollDirection direction) {
+            if (direction == ScrollDirection.DOWN && FeatureUtilities.isChromeHomeEnabled()) {
+                return false;
+            }
+
+            return super.isSwipeEnabled(direction);
+        }
+    }
 }