Refactor SPen related code into a separate class

BUG=398169

Review URL: https://codereview.chromium.org/428883013

Cr-Commit-Position: refs/heads/master@{#288363}
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@288363 0039d316-1c4b-4281-b951-d872f2087c98

content/public/android/java/src/org/chromium/content/browser/ContentViewCore.java

@@ -1203,8 +1203,8 @@ public class ContentViewCore
                 cancelRequestToScrollFocusedEditableNodeIntoView();
             }
 
-            if (isSPenSupported(mContext))
-                eventAction = convertSPenEventAction(eventAction);
+            if (SPenSupport.isSPenSupported(mContext))
+                eventAction = SPenSupport.convertSPenEventAction(eventAction);
             if (!isValidTouchEventActionForNative(eventAction)) return false;
 
             if (mNativeContentViewCore == 0) return false;

content/public/android/java/src/org/chromium/content/browser/SPenSupport.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.content.browser;
+
+import android.content.Context;
+import android.content.pm.FeatureInfo;
+import android.os.Build;
+import android.view.MotionEvent;
+
+/**
+ * Support S-Pen event detection and conversion.
+ */
+public final class SPenSupport {
+
+    // These values are obtained from Samsung.
+    private static final int SPEN_ACTION_DOWN = 211;
+    private static final int SPEN_ACTION_UP = 212;
+    private static final int SPEN_ACTION_MOVE = 213;
+    private static final int SPEN_ACTION_CANCEL = 214;
+    private static Boolean sIsSPenSupported;
+
+    /**
+     * @return Whether SPen is supported on the device.
+     */
+    public static boolean isSPenSupported(Context context) {
+        if (sIsSPenSupported == null) {
+            sIsSPenSupported = detectSPenSupport(context);
+        }
+        return sIsSPenSupported.booleanValue();
+    }
+
+    private static boolean detectSPenSupport(Context context) {
+        if (!"SAMSUNG".equalsIgnoreCase(Build.MANUFACTURER)) {
+            return false;
+        }
+
+        final FeatureInfo[] infos = context.getPackageManager().getSystemAvailableFeatures();
+        for (FeatureInfo info : infos) {
+            if ("com.sec.feature.spen_usp".equalsIgnoreCase(info.name)) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    /**
+     * Convert SPen event action into normal event action.
+     *
+     * @param eventActionMasked Input event action. It is assumed that it is masked as the values
+                                cannot be ORed.
+     * @return Event action after the conversion.
+     */
+    public static int convertSPenEventAction(int eventActionMasked) {
+        // S-Pen support: convert to normal stylus event handling
+        switch (eventActionMasked) {
+            case SPEN_ACTION_DOWN:
+                return MotionEvent.ACTION_DOWN;
+            case SPEN_ACTION_UP:
+                return MotionEvent.ACTION_UP;
+            case SPEN_ACTION_MOVE:
+                return MotionEvent.ACTION_MOVE;
+            case SPEN_ACTION_CANCEL:
+                return MotionEvent.ACTION_CANCEL;
+            default:
+                return eventActionMasked;
+        }
+    }
+}