[Modern] Improve tab switcher theme color animations

This change removes the use of transparency on the location bar when
modern is enabled. This simplifies the logic required to run animations
and fixes a flickering issue when entering and exiting the tab switcher.

This change also changes the background color of the asset to white.
This allows it to be easily tinted which will also be required for the
composited version.

BUG=803098,803091

Change-Id: Ia56660da21f615840f6ea2902a3252b8809d337f
Reviewed-on: https://chromium-review.googlesource.com/899772
Commit-Queue: Matthew Jones <mdjones@chromium.org>
Reviewed-by: Ted Choc <tedchoc@chromium.org>
Reviewed-by: Theresa <twellington@chromium.org>
Cr-Commit-Position: refs/heads/master@{#534839}

chrome/android/java/res/drawable/modern_toolbar_background.xml

@@ -6,7 +6,7 @@
 <shape
     xmlns:android="http://schemas.android.com/apk/res/android"
     android:shape="rectangle" >
-    <solid android:color="@color/modern_light_grey" />
+    <solid android:color="@android:color/white" />
     <size
         android:width="@dimen/modern_toolbar_background_size"
         android:height="@dimen/modern_toolbar_background_size" />
@@ -16,4 +16,4 @@
         android:bottom="0dp"
         android:left="@dimen/modern_toolbar_background_lateral_inset"
         android:right="@dimen/modern_toolbar_background_lateral_inset" />
-</shape>
+</shape>
\ No newline at end of file

chrome/android/java/src/org/chromium/chrome/browser/toolbar/ToolbarPhone.java

@@ -284,6 +284,9 @@ public class ToolbarPhone extends ToolbarLayout
      */
     private int mModernLocationBarExtraFocusedStartMargin;
 
+    /** The current color of the location bar. */
+    private int mCurrentLocationBarColor;
+
     /**
      * Used to specify the visual state of the toolbar.
      */
@@ -388,8 +391,7 @@ public class ToolbarPhone extends ToolbarLayout
             Resources res = getResources();
             mModernLocationBarBackgroundHeight =
                     res.getDimensionPixelSize(R.dimen.modern_toolbar_background_size);
-            mLocationBarBackground =
-                    ApiCompatibilityUtils.getDrawable(res, R.drawable.modern_toolbar_background);
+            mLocationBarBackground = createModernLocationBarBackground();
             mLocationBarBackground.getPadding(mLocationBarBackgroundPadding);
             mLocationBarBackground.mutate();
             mLocationBar.setPadding(mLocationBarBackgroundPadding.left,
@@ -418,6 +420,37 @@ public class ToolbarPhone extends ToolbarLayout
         }
     }
 
+    /**
+     * @return The drawable for the modern location bar background.
+     */
+    public Drawable createModernLocationBarBackground() {
+        Drawable drawable = ApiCompatibilityUtils.getDrawable(
+                getResources(), R.drawable.modern_toolbar_background);
+        drawable.setColorFilter(
+                ApiCompatibilityUtils.getColor(getResources(), R.color.modern_light_grey),
+                PorterDuff.Mode.SRC_IN);
+        return drawable;
+    }
+
+    /**
+     * Set the background color of the location bar to appropriately match the theme color.
+     */
+    private void updateModernLocationBarColor(int color) {
+        if (mCurrentLocationBarColor == color) return;
+        mCurrentLocationBarColor = color;
+        mLocationBarBackground.setColorFilter(color, PorterDuff.Mode.SRC_IN);
+    }
+
+    /**
+     * Get the corresponding location bar color for a toolbar color.
+     * @param toolbarColor The color of the toolbar.
+     * @return The location bar color.
+     */
+    private int getLocationBarColorForToolbarColor(int toolbarColor) {
+        return ColorUtils.getTextBoxColorForToolbarBackground(
+                getResources(), false, toolbarColor, mLocationBar.useModernDesign());
+    }
+
     private void inflateTabSwitchingResources() {
         mToggleTabStackButton = (ImageView) findViewById(R.id.tab_switcher_button);
         mNewTabButton = (NewTabButton) findViewById(R.id.new_tab_button);
@@ -1435,6 +1468,12 @@ public class ToolbarPhone extends ToolbarLayout
             } else {
                 backgroundAlpha = mLocationBarBackgroundAlpha;
             }
+
+            // If modern is enabled the location bar background is opaque.
+            // TODO(mdjones): The location bar background should always be opaque. We have the
+            // capability to determine the foreground color without alpha and it reduces the amount
+            // of state that this class tracks.
+            if (mLocationBar.useModernDesign()) backgroundAlpha = 255;
             mLocationBarBackground.setAlpha(backgroundAlpha);
 
             if (shouldDrawLocationBarBackground()) {
@@ -2214,6 +2253,9 @@ public class ToolbarPhone extends ToolbarLayout
         final int finalColor = getToolbarDataProvider().getPrimaryColor();
         if (initialColor == finalColor) return;
 
+        final int initialLocationBarColor = getLocationBarColorForToolbarColor(initialColor);
+        final int finalLocationBarColor = getLocationBarColorForToolbarColor(finalColor);
+
         if (!isVisualStateValidForBrandColorTransition(mVisualState)) return;
 
         if (!shouldAnimate) {
@@ -2239,6 +2281,10 @@ public class ToolbarPhone extends ToolbarLayout
                 }
                 updateToolbarBackground(
                         ColorUtils.getColorWithOverlay(initialColor, finalColor, fraction));
+                if (mLocationBar.useModernDesign()) {
+                    updateModernLocationBarColor(ColorUtils.getColorWithOverlay(
+                            initialLocationBarColor, finalLocationBarColor, fraction));
+                }
             }
         });
         mBrandColorTransitionAnimation.addListener(new AnimatorListenerAdapter() {
@@ -2473,6 +2519,9 @@ public class ToolbarPhone extends ToolbarLayout
         }
 
         mMenuButton.setTint(mUseLightToolbarDrawables ? mLightModeTint : mDarkModeTint);
+        if (mLocationBar.useModernDesign()) {
+            updateModernLocationBarColor(getLocationBarColorForToolbarColor(currentPrimaryColor));
+        }
 
         setMenuButtonHighlightDrawable(mHighlightingMenu);
         if (mShowMenuBadge && inOrEnteringStaticTab) {

chrome/android/java/src/org/chromium/chrome/browser/util/ColorUtils.java

@@ -72,13 +72,18 @@ public class ColorUtils {
      */
     public static int getTextBoxColorForToolbarBackground(
             Resources res, boolean isNtp, int color, boolean useModernDesign) {
+        // If modern is enabled, it is a special case. It's toolbar is white with a darker text box
+        // background.
+        boolean usingDefaultThemeColor =
+                ColorUtils.isUsingDefaultToolbarColor(res, useModernDesign, false, color);
+        if (usingDefaultThemeColor && useModernDesign) {
+            return ApiCompatibilityUtils.getColor(res, R.color.modern_light_grey);
+        }
+
         if (shouldUseOpaqueTextboxBackground(color)) {
             // NTP should have no visible textbox in the toolbar, so just return the toolbar's
             // background color.
-            if (isNtp) return ApiCompatibilityUtils.getColor(res, R.color.ntp_bg);
-
-            return useModernDesign ? ApiCompatibilityUtils.getColor(res, R.color.modern_light_grey)
-                                   : Color.WHITE;
+            return isNtp ? ApiCompatibilityUtils.getColor(res, R.color.ntp_bg) : Color.WHITE;
         }
         return getColorWithOverlay(color, Color.WHITE, LOCATION_BAR_TRANSPARENT_BACKGROUND_ALPHA);
     }

chrome/android/javatests/src/org/chromium/chrome/browser/compositor/layouts/MockResourcesForLayout.java

@@ -68,6 +68,11 @@ public class MockResourcesForLayout extends MockResources {
         mFloats.put(org.chromium.chrome.R.dimen.contextual_search_bar_banner_padding, 12.f);
         mFloats.put(org.chromium.chrome.R.dimen.contextual_search_end_button_width, 41.f);
         mFloats.put(org.chromium.chrome.R.dimen.toolbar_height_no_shadow, 56.f);
+        mIntegers.put(R.color.modern_light_grey, 0xFFF1F3F4);
+        mIntegers.put(R.color.modern_primary_color, Color.WHITE);
+        mIntegers.put(R.color.default_primary_color, 0xFFF2F2F2);
+        mIntegers.put(R.color.incognito_primary_color, 0xFF505050);
+        mIntegers.put(R.color.ntp_bg, 0xFFF2F2F2);
     }
 
     @Override