Update more colors in Data Usage Summary

- use colors from the Settings Theme
- code cleaning for use the Theme accent color constant
instead of raw color value

Change-Id: I04ec913f0b8048b6e50069213e9d92992168fe18
diff --git a/src/com/android/settings/DataUsageSummary.java b/src/com/android/settings/DataUsageSummary.java
index 86a73c2..1d41816 100644
--- a/src/com/android/settings/DataUsageSummary.java
+++ b/src/com/android/settings/DataUsageSummary.java
@@ -189,6 +189,9 @@
     private static final int LOADER_CHART_DATA = 2;
     private static final int LOADER_SUMMARY = 3;
 
+    private static final int FOREGROUND_BYTES_COLOR = 0xff009688;
+    private static final int DEFAULT_BYTES_COLOR = 0xffced7db;
+
     private INetworkManagementService mNetworkService;
     private INetworkStatsService mStatsService;
     private NetworkPolicyManager mPolicyManager;
@@ -1176,8 +1179,8 @@
             mAppPieChart.setOriginAngle(175);
 
             mAppPieChart.removeAllSlices();
-            mAppPieChart.addSlice(foregroundBytes, Color.parseColor("#d88d3a"));
-            mAppPieChart.addSlice(defaultBytes, Color.parseColor("#666666"));
+            mAppPieChart.addSlice(foregroundBytes, FOREGROUND_BYTES_COLOR);
+            mAppPieChart.addSlice(defaultBytes, DEFAULT_BYTES_COLOR);
 
             mAppPieChart.generatePath();