Localized optimizations in views and bitmaps

* Don't call context.getResources() redundantly when unnecessary;
  similarly for Resources.getCompatibilityInfo()

* During bitmap creation, don't bother clearing to 0: it's unnecessary
  because now that the raw bits are stored in a VM-side byte array, it
  was cleared at initialization time.  Also, don't use the sanity-
  checking public entry point to erase to a color, because we know
  that we're by definition in a "legal" path to erase to the initial
  contents and don't need to incur the overhead of the (inappropriate)
  sanity checking.

Change-Id: Idaca4d64fdecefd5d51337646ead32e1db510e02

3 files changed, 13 insertions, 8 deletions

diff --git a/core/java/android/widget/EdgeEffect.java b/core/java/android/widget/EdgeEffect.java
index fd2abc2..326587e 100644
--- a/core/java/android/widget/EdgeEffect.java
+++ b/core/java/android/widget/EdgeEffect.java
@@ -129,7 +129,7 @@ public class EdgeEffect {
         mEdge = res.getDrawable(R.drawable.overscroll_edge);
         mGlow = res.getDrawable(R.drawable.overscroll_glow);
 
-        mMinWidth = (int) (context.getResources().getDisplayMetrics().density * MIN_WIDTH + 0.5f);
+        mMinWidth = (int) (res.getDisplayMetrics().density * MIN_WIDTH + 0.5f);
         mInterpolator = new DecelerateInterpolator();
     }
 
diff --git a/core/java/android/widget/TextView.java b/core/java/android/widget/TextView.java
index bc8721a..b106cc5 100644
--- a/core/java/android/widget/TextView.java
+++ b/core/java/android/widget/TextView.java
@@ -24,6 +24,7 @@ import android.content.Context;
 import android.content.Intent;
 import android.content.pm.PackageManager;
 import android.content.res.ColorStateList;
+import android.content.res.CompatibilityInfo;
 import android.content.res.Resources;
 import android.content.res.TypedArray;
 import android.content.res.XmlResourceParser;
@@ -449,18 +450,19 @@ public class TextView extends View implements ViewTreeObserver.OnPreDrawListener
         super(context, attrs, defStyle);
         mText = "";
 
+        final Resources res = getResources();
+        final CompatibilityInfo compat = res.getCompatibilityInfo();
+
         mTextPaint = new TextPaint(Paint.ANTI_ALIAS_FLAG);
-        mTextPaint.density = getResources().getDisplayMetrics().density;
-        mTextPaint.setCompatibilityScaling(
-                getResources().getCompatibilityInfo().applicationScale);
+        mTextPaint.density = res.getDisplayMetrics().density;
+        mTextPaint.setCompatibilityScaling(compat.applicationScale);
 
         // If we get the paint from the skin, we should set it to left, since
         // the layout always wants it to be left.
         // mTextPaint.setTextAlign(Paint.Align.LEFT);
 
         mHighlightPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
-        mHighlightPaint.setCompatibilityScaling(
-                getResources().getCompatibilityInfo().applicationScale);
+        mHighlightPaint.setCompatibilityScaling(compat.applicationScale);
 
         mMovement = getDefaultMovementMethod();
         mTransformation = null;
diff --git a/graphics/java/android/graphics/Bitmap.java b/graphics/java/android/graphics/Bitmap.java
index 79acd55..380b3d8 100644
--- a/graphics/java/android/graphics/Bitmap.java
+++ b/graphics/java/android/graphics/Bitmap.java
@@ -604,10 +604,13 @@ public final class Bitmap implements Parcelable {
         }
         Bitmap bm = nativeCreate(null, 0, width, width, height, config.nativeInt, true);
         if (config == Config.ARGB_8888 && !hasAlpha) {
-            bm.eraseColor(0xff000000);
+            nativeErase(bm.mNativeBitmap, 0xff000000);
             nativeSetHasAlpha(bm.mNativeBitmap, hasAlpha);
         } else {
-            bm.eraseColor(0);
+            // No need to initialize it to zeroes; it is backed by a VM byte array
+            // which is by definition preinitialized to all zeroes.
+            //
+            //nativeErase(bm.mNativeBitmap, 0);
         }
         return bm;
     }