Provide max gesture bounds and option to ignore touch size during pinch

ui/android/java/src/org/chromium/ui/gfx/ViewConfigurationHelper.java

 // Copyright 2014 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.ui.gfx;
 
 import android.content.ComponentCallbacks;
 import android.content.Context;
 import android.content.res.Configuration;
 import android.content.res.Resources;
+import android.os.Build;
 import android.util.TypedValue;
 import android.view.ViewConfiguration;
 
 import org.chromium.base.CalledByNative;
 import org.chromium.base.JNINamespace;
 import org.chromium.ui.R;
 
 /**
  * This class facilitates access to ViewConfiguration-related properties, also
  * providing native-code notifications when such properties have changed.
@@ skipping 108 matching lines @@
         try {
             return res.getDimensionPixelSize(id);
         } catch (Resources.NotFoundException e) {
             assert false : "MinScalingTouchMajor resource lookup failed.";
             return (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP,
                     MIN_SCALING_TOUCH_MAJOR_DIP, res.getDisplayMetrics());
         }
     }
 
     @CalledByNative
+    private static boolean shouldUseTouchMajorInScalingSpan() {
+        // Android's ScaleGestureDetector started using touch major values in
+        // JBMR1. Many devices from versions prior report wildly inconsistent
+        // touch sizes, so disable touch major use in such scenarios.
+        return Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN_MR1;
+    }
+
+    @CalledByNative
     private static ViewConfigurationHelper createWithListener(Context context) {
         ViewConfigurationHelper viewConfigurationHelper = new ViewConfigurationHelper(context);
         viewConfigurationHelper.registerListener();
         return viewConfigurationHelper;
     }
 
     private native void nativeUpdateSharedViewConfiguration(
             int scaledMaximumFlingVelocity, int scaledMinimumFlingVelocity,
             int scaledTouchSlop, int scaledDoubleTapSlop,
             int scaledMinScalingSpan, int scaledMinScalingTouchMajor);
 }