Make HolographicOutlineHelper a singleton.

It's a pretty heavy object, including three Paints at 74
bytes apiece, and we allocate one for every workspace and
every icon. We really only need one.

Change-Id: Ic9e12d478c3be27b13133718875c91540f7ccf4c
diff --git a/src/com/android/launcher3/HolographicOutlineHelper.java b/src/com/android/launcher3/HolographicOutlineHelper.java
index 0344cd5..47c40b6 100644
--- a/src/com/android/launcher3/HolographicOutlineHelper.java
+++ b/src/com/android/launcher3/HolographicOutlineHelper.java
@@ -43,6 +43,8 @@
     private static final int MEDIUM = 1;
     private static final int EXTRA_THICK = 2;
 
+    static HolographicOutlineHelper INSTANCE;
+
     static {
         final float scale = LauncherAppState.getScreenDensity();
 
@@ -56,9 +58,11 @@
         sExtraThickInnerBlurMaskFilter = new BlurMaskFilter(scale * 6.0f, BlurMaskFilter.Blur.NORMAL);
         sThickInnerBlurMaskFilter = new BlurMaskFilter(scale * 4.0f, BlurMaskFilter.Blur.NORMAL);
         sMediumInnerBlurMaskFilter = new BlurMaskFilter(scale * 2.0f, BlurMaskFilter.Blur.NORMAL);
+
+        INSTANCE = new HolographicOutlineHelper();
     }
 
-    HolographicOutlineHelper() {
+    private HolographicOutlineHelper() {
         mHolographicPaint.setFilterBitmap(true);
         mHolographicPaint.setAntiAlias(true);
         mBlurPaint.setFilterBitmap(true);
@@ -68,6 +72,10 @@
         mErasePaint.setAntiAlias(true);
     }
 
+    public static HolographicOutlineHelper obtain() {
+        return INSTANCE;
+    }
+
     /**
      * Returns the interpolated holographic highlight alpha for the effect we want when scrolling
      * pages.