Update Launcher to use theme colors.

Instead of using hard-coded variants of colors, use the theme color
that corresponds (colorAccent, colorPrimary, etc).

Updated:
- "Search for more apps" text
- App info drop target hover color
- PageIndicatorDots
- All apps & widget scroll bar & scroll popup colors
- All apps section text color
- widget picker background color

TODO:
- widget picker header color

BUG: 28625102
Change-Id: I74b543ff71b8caef8cd950c8183ac84c759cb4d5
diff --git a/src/com/android/launcher3/Utilities.java b/src/com/android/launcher3/Utilities.java
index 3511375..0306d57 100644
--- a/src/com/android/launcher3/Utilities.java
+++ b/src/com/android/launcher3/Utilities.java
@@ -30,6 +30,7 @@
 import android.content.pm.PackageManager.NameNotFoundException;
 import android.content.pm.ResolveInfo;
 import android.content.res.Resources;
+import android.content.res.TypedArray;
 import android.database.Cursor;
 import android.graphics.Bitmap;
 import android.graphics.BitmapFactory;
@@ -839,4 +840,11 @@
             return getBitmap().getWidth();
         }
     }
+
+    public static int getColorAccent(Context context) {
+        TypedArray ta = context.obtainStyledAttributes(new int[]{android.R.attr.colorAccent});
+        int colorAccent = ta.getColor(0, 0);
+        ta.recycle();
+        return colorAccent;
+    }
 }