Bottom browser controls position based on window height

chrome/android/java/src/org/chromium/chrome/browser/compositor/scene_layer/ToolbarSceneLayer.java

Index: chrome/android/java/src/org/chromium/chrome/browser/compositor/scene_layer/ToolbarSceneLayer.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/compositor/scene_layer/ToolbarSceneLayer.java b/chrome/android/java/src/org/chromium/chrome/browser/compositor/scene_layer/ToolbarSceneLayer.java
index dca21ab25cf2137f034dcf6b1c1aedfe1ef3e34a..4e65c0f6e1334bead7ba1911b30f89173b46e650 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/compositor/scene_layer/ToolbarSceneLayer.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/compositor/scene_layer/ToolbarSceneLayer.java
@@ -45,9 +45,6 @@ public class ToolbarSceneLayer extends SceneOverlayLayer implements SceneOverlay
     /** A LayoutRenderHost for accessing drawing information about the toolbar. */
     private LayoutRenderHost mRenderHost;
 
-    /** The size of the viewport (full-screen minus status bar). */
-    private RectF mViewport;
-
     /**
      * @param context An Android context to use.
      * @param provider A LayoutProvider for accessing the current layout.
@@ -58,7 +55,6 @@ public class ToolbarSceneLayer extends SceneOverlayLayer implements SceneOverlay
         mContext = context;
         mLayoutProvider = provider;
         mRenderHost = renderHost;
-        mViewport = new RectF();
     }
 
     /**
@@ -71,10 +67,12 @@ public class ToolbarSceneLayer extends SceneOverlayLayer implements SceneOverlay
      * @param forceHideAndroidBrowserControls True if the Android browser controls are being hidden.
      * @param sizingFlags The sizing flags for the toolbar.
      * @param isTablet If the device is a tablet.
+     * @param windowHeight The height of the window.
      */
     private void update(int browserControlsBackgroundColor, float browserControlsUrlBarAlpha,
             ChromeFullscreenManager fullscreenManager, ResourceManager resourceManager,
-            boolean forceHideAndroidBrowserControls, ViewportMode viewportMode, boolean isTablet) {
+            boolean forceHideAndroidBrowserControls, ViewportMode viewportMode, boolean isTablet,
+            float windowHeight) {
         if (!DeviceClassManager.enableFullscreen()) return;
 
         if (fullscreenManager == null) return;
@@ -86,21 +84,21 @@ public class ToolbarSceneLayer extends SceneOverlayLayer implements SceneOverlay
             assert mProgressBarDrawingInfo == null;
         }
 
-        mLayoutProvider.getViewportPixel(mViewport);
-
         // Texture is always used unless it is completely off-screen.
         boolean useTexture = !fullscreenManager.areBrowserControlsOffScreen()
                 && viewportMode != ViewportMode.ALWAYS_FULLSCREEN;
         boolean showShadow = fullscreenManager.drawControlsAsTexture()
                 || forceHideAndroidBrowserControls;
 
-        // Note that the bottom controls offset is not passed here. Conveniently, the viewport
-        // size changes will push the controls off screen when they are at the bottom; see
-        // mViewport.height().
+        // Use either top or bottom offset depending on the browser controls state.
+        float controlsOffset = fullscreenManager.areBrowserControlsAtBottom()
+                ? fullscreenManager.getBottomControlOffset()
+                : fullscreenManager.getTopControlOffset();
+
         nativeUpdateToolbarLayer(mNativePtr, resourceManager, R.id.control_container,
                 browserControlsBackgroundColor, R.drawable.textbox, browserControlsUrlBarAlpha,
-                fullscreenManager.getTopControlOffset(), mViewport.height(), useTexture,
-                showShadow, fullscreenManager.areBrowserControlsAtBottom());
+                controlsOffset, windowHeight, useTexture, showShadow,
+                fullscreenManager.areBrowserControlsAtBottom());
 
         if (mProgressBarDrawingInfo == null) return;
         nativeUpdateProgressBar(mNativePtr,
@@ -141,8 +139,8 @@ public class ToolbarSceneLayer extends SceneOverlayLayer implements SceneOverlay
     // SceneOverlay implementation.
 
     @Override
-    public SceneOverlayLayer getUpdatedSceneOverlayTree(LayerTitleCache layerTitleCache,
-            ResourceManager resourceManager, float yOffset) {
+    public SceneOverlayLayer getUpdatedSceneOverlayTree(RectF viewport, RectF visibleViewport,
+            LayerTitleCache layerTitleCache, ResourceManager resourceManager, float yOffset) {
         boolean forceHideBrowserControlsAndroidView =
                 mLayoutProvider.getActiveLayout().forceHideBrowserControlsAndroidView();
         ViewportMode viewportMode = mLayoutProvider.getActiveLayout().getViewportMode();
@@ -150,7 +148,7 @@ public class ToolbarSceneLayer extends SceneOverlayLayer implements SceneOverlay
         update(mRenderHost.getBrowserControlsBackgroundColor(),
                 mRenderHost.getBrowserControlsUrlBarAlpha(), mLayoutProvider.getFullscreenManager(),
                 resourceManager, forceHideBrowserControlsAndroidView, viewportMode,
-                DeviceFormFactor.isTablet(mContext));
+                DeviceFormFactor.isTablet(mContext), viewport.height());
 
         return this;
     }