Send correct key-codes when doing composition events instead of always 0.

content/public/android/java/src/org/chromium/content/browser/input/ImeAdapter.java

Index: content/public/android/java/src/org/chromium/content/browser/input/ImeAdapter.java
diff --git a/content/public/android/java/src/org/chromium/content/browser/input/ImeAdapter.java b/content/public/android/java/src/org/chromium/content/browser/input/ImeAdapter.java
index d85273be9f59e92ddf388eeab157d6da9d7be89a..2590d563fc07e94821624d9677d3c2284357a83a 100644
--- a/content/public/android/java/src/org/chromium/content/browser/input/ImeAdapter.java
+++ b/content/public/android/java/src/org/chromium/content/browser/input/ImeAdapter.java
@@ -116,6 +116,7 @@ public class ImeAdapter {
     static int sModifierCtrl;
     static int sModifierCapsLockOn;
     static int sModifierNumLockOn;
+    static KeyCharacterMap sKeyCharacterMap;
 
     private long mNativeImeAdapterAndroid;
     private InputMethodManagerWrapper mInputMethodManagerWrapper;
@@ -124,6 +125,10 @@ public class ImeAdapter {
     private final Handler mHandler;
     private DelayedDismissInput mDismissInput = null;
     private int mTextInputType;
+    private String mLastComposeText;
+
+    @VisibleForTesting
+    int mLastComposeKeyCode;
 
     @VisibleForTesting
     boolean mIsShowWithoutHideOutstanding = false;
@@ -317,6 +322,42 @@ public class ImeAdapter {
         else return COMPOSITION_KEY_CODE;
     }
 
+    private static int androidKeyCodeForCharacter(char chr) {
+        if (sKeyCharacterMap == null) {
+            sKeyCharacterMap = KeyCharacterMap.load(KeyCharacterMap.VIRTUAL_KEYBOARD);
+        }
+        char[] chars = new char[1];

[jdduke (slow), 2014/07/08 19:26:23]

This will create garbage every time we fetch the key code, which is really
unfortunate.  Also, |KeyCharacterMap.getEvents()| has been deprecated since API
Level 11 so we probably shouldn't start using it now.

+        chars[0] = chr;
+        KeyEvent[] events = sKeyCharacterMap.getEvents(chars);
+        return events[0].getKeyCode();
+    }
+
+    @VisibleForTesting
+    public static int getTypedKeycodeGuess(String oldtext, String newtext) {
+        // Starting typing a new composition should add only a single character.  Any composition
+        // beginning with text longer than that must come from something other than typing so
+        // return 0.
+        if (oldtext == null) {
+            if (newtext.length() == 1) {
+                return androidKeyCodeForCharacter(newtext.charAt(0));
+            } else {
+                return 0;
+            }
+        }
+
+        // The content has grown in length: assume the last character is the key that caused it.
+        if (newtext.length() > oldtext.length() && newtext.startsWith(oldtext))
+            return androidKeyCodeForCharacter(newtext.charAt(newtext.length() - 1));
+
+        // The content has shrunk in length: assume that backspace was pressed.
+        if (oldtext.length() > newtext.length() && oldtext.startsWith(newtext))
+            return KeyEvent.KEYCODE_DEL;
+
+        // The content is unchanged or has undergone a complex change (i.e. not a simple tail
+        // modification) so return an unknown key-code.
+        return 0;
+    }
+
     void sendKeyEventWithKeyCode(int keyCode, int flags) {
         long eventTime = SystemClock.uptimeMillis();
         translateAndSendNativeEvents(new KeyEvent(eventTime, eventTime,
@@ -346,15 +387,22 @@ public class ImeAdapter {
             sendKeyEventWithKeyCode(keyCode,
                     KeyEvent.FLAG_SOFT_KEYBOARD | KeyEvent.FLAG_KEEP_TOUCH_MODE);
         } else {
-            nativeSendSyntheticKeyEvent(mNativeImeAdapterAndroid, sEventTypeRawKeyDown,
-                    timeStampMs, keyCode, 0);
+            keyCode = getTypedKeycodeGuess(mLastComposeText, textStr);
+            mLastComposeText = textStr;
+            mLastComposeKeyCode = keyCode;
+
+            if (keyCode != 0)
+                nativeSendSyntheticKeyEvent(mNativeImeAdapterAndroid, sEventTypeRawKeyDown,
+                        timeStampMs, keyCode, 0);
             if (isCommit) {
                 nativeCommitText(mNativeImeAdapterAndroid, textStr);
+                mLastComposeText = null;
             } else {
                 nativeSetComposingText(mNativeImeAdapterAndroid, text, textStr, newCursorPosition);
             }
-            nativeSendSyntheticKeyEvent(mNativeImeAdapterAndroid, sEventTypeKeyUp,
-                    timeStampMs, keyCode, 0);
+            if (keyCode != 0)
+                nativeSendSyntheticKeyEvent(mNativeImeAdapterAndroid, sEventTypeKeyUp,
+                        timeStampMs, keyCode, 0);
         }
 
         return true;
@@ -362,6 +410,7 @@ public class ImeAdapter {
 
     void finishComposingText() {
         if (mNativeImeAdapterAndroid == 0) return;
+        mLastComposeText = null;
         nativeFinishComposingText(mNativeImeAdapterAndroid);
     }
 
@@ -553,6 +602,7 @@ public class ImeAdapter {
     @CalledByNative
     private void cancelComposition() {
         if (mInputConnection != null) mInputConnection.restartInput();
+        mLastComposeText = null;
     }
 
     @CalledByNative