Remove redundant field initialization in Java code.

chrome/android/java/src/org/chromium/chrome/browser/compositor/layouts/phone/StackLayout.java

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 package org.chromium.chrome.browser.compositor.layouts.phone;
 
 import android.content.Context;
 import android.graphics.Rect;
 import android.graphics.RectF;
 import android.os.SystemClock;
@@ skipping 64 matching lines @@
     private static final float SWITCH_STACK_FLING_DT = 1.0f / 30.0f;
 
     /** The array of potentially visible stacks. The code works for only 2 stacks. */
     private final Stack[] mStacks;
 
     /** Rectangles that defines the area where each stack need to be laid out. */
     private final RectF[] mStackRects;
 
     private int mStackAnimationCount;
 
-    private float mFlingSpeed = 0; // pixel/ms
+    private float mFlingSpeed; // pixel/ms
 
     /** Whether the current fling animation is the result of switching stacks. */
     private boolean mFlingFromModelChange;
 
     private boolean mClicked;
 
     // If not overscroll, then mRenderedScrollIndex == mScrollIndex;
     // Otherwise, mRenderedScrollIndex is updated with the actual index passed in
     // from the event handler; and mRenderedScrollIndex is the value we get
     // after map mScrollIndex through a decelerate function.
     // Here we use float as index so we can smoothly animate the transition between stack.
-    private float mRenderedScrollOffset = 0.0f;
-    private float mScrollIndexOffset = 0.0f;
+    private float mRenderedScrollOffset;
+    private float mScrollIndexOffset;
 
     private final int mMinMaxInnerMargin;
     private float mInnerMarginPercent;
     private float mStackOffsetYPercent;
 
     private SwipeMode mInputMode = SwipeMode.NONE;
     private float mLastOnDownX;
     private float mLastOnDownY;
     private long mLastOnDownTimeStamp;
     private final float mMinShortPressThresholdSqr; // Computed from Android ViewConfiguration
     private final float mMinDirectionThreshold; // Computed from Android ViewConfiguration
 
     // Pre-allocated temporary arrays that store id of visible tabs.
     // They can be used to call populatePriorityVisibilityList.
     // We use StackTab[] instead of ArrayList<StackTab> because the sorting function does
     // an allocation to iterate over the elements.
     // Do not use out of the context of {@link #updateTabPriority}.
-    private StackTab[] mSortedPriorityArray = null;
+    private StackTab[] mSortedPriorityArray;
 
     private final ArrayList<Integer> mVisibilityArray = new ArrayList<Integer>();
     private final VisibilityComparator mVisibilityComparator = new VisibilityComparator();
     private final OrderComparator mOrderComparator = new OrderComparator();
     private Comparator<StackTab> mSortingComparator = mVisibilityComparator;
 
     private static final int LAYOUTTAB_ASYNCHRONOUS_INITIALIZATION_BATCH_SIZE = 4;
-    private boolean mDelayedLayoutTabInitRequired = false;
+    private boolean mDelayedLayoutTabInitRequired;
 
     private Boolean mTemporarySelectedStack;
 
     // Orientation Variables
-    private PortraitViewport mCachedPortraitViewport = null;
-    private PortraitViewport mCachedLandscapeViewport = null;
+    private PortraitViewport mCachedPortraitViewport;
+    private PortraitViewport mCachedLandscapeViewport;
 
     private final ViewGroup mViewContainer;
 
     private final TabListSceneLayer mSceneLayer;
 
     /**
      * @param context     The current Android's context.
      * @param updateHost  The {@link LayoutUpdateHost} view for this layout.
      * @param renderHost  The {@link LayoutRenderHost} view for this layout.
      * @param eventFilter The {@link EventFilter} that is needed for this view.
@@ skipping 1086 matching lines @@
     protected void updateSceneLayer(RectF viewport, RectF contentViewport,
             LayerTitleCache layerTitleCache, TabContentManager tabContentManager,
             ResourceManager resourceManager, ChromeFullscreenManager fullscreenManager) {
         super.updateSceneLayer(viewport, contentViewport, layerTitleCache, tabContentManager,
                 resourceManager, fullscreenManager);
         assert mSceneLayer != null;
         mSceneLayer.pushLayers(getContext(), viewport, contentViewport, this, layerTitleCache,
                 tabContentManager, resourceManager, fullscreenManager);
     }
 }