Fix support_library build

Change-Id: Ie5e0c1badd223c3013b76b19696ccfbf5f3c883e
diff --git a/v7/mediarouter/src/android/support/v7/app/MediaRouteVolumeSlider.java b/v7/mediarouter/src/android/support/v7/app/MediaRouteVolumeSlider.java
index 9e650fc..57c03cc 100644
--- a/v7/mediarouter/src/android/support/v7/app/MediaRouteVolumeSlider.java
+++ b/v7/mediarouter/src/android/support/v7/app/MediaRouteVolumeSlider.java
@@ -18,7 +18,6 @@
 
 import android.content.Context;
 import android.content.res.TypedArray;
-import android.graphics.Color;
 import android.graphics.ColorFilter;
 import android.graphics.PorterDuff;
 import android.graphics.PorterDuffColorFilter;
@@ -41,7 +40,7 @@
     }
 
     public MediaRouteVolumeSlider(Context context, AttributeSet attrs) {
-        this(context, attrs, android.support.v7.appcompat.R.attr.seekBarStyle);
+        this(context, attrs, R.attr.seekBarStyle);
     }
 
     public MediaRouteVolumeSlider(Context context, AttributeSet attrs, int defStyleAttr) {