Introduce an input method callback required by Android 34

* java/org/gnu/emacs/EmacsInputConnection.java (replaceText):
New function.

* java/org/gnu/emacs/EmacsNative.java (replaceText): Declare
native function.

* src/androidgui.h (enum android_ime_operation): New operation
ANDROID_IME_REPLACE_TEXT.

* src/androidterm.c (android_handle_ime_event): Decode text when
encountering an ANDROID_IME_REPLACE_TEXT operation.  Return if
decoding overflowed rather than presenting Qnil to textconv
functions.
(replaceText): New JNI function.

* src/frame.h (enum text_conversion_operation): New operation
TEXTCONV_REPLACE_TEXT.

* src/textconv.c (really_commit_text): Move point to start if
the composing region is set.
(really_replace_text): New function.
(handle_pending_conversion_events_1) <TEXTCONV_REPLACE_TEXT>:
New case.
(replace_text): New function.

* src/textconv.h: Update prototypes.

java/org/gnu/emacs/EmacsInputConnection.java

@@ -628,6 +628,21 @@ public final class EmacsInputConnection implements InputConnection
     batchEditCount = 0;
   }
 
+  @Override
+  public boolean
+  replaceText (int start, int end, CharSequence text,
+	       int newCursorPosition, TextAttribute attributes)
+  {
+    if (EmacsService.DEBUG_IC)
+      Log.d (TAG, ("replaceText: " + text + ":: " + start + ","
+		   + end + "," + newCursorPosition));
+
+    EmacsNative.replaceText (windowHandle, start, end,
+			     text.toString (), newCursorPosition,
+			     attributes);
+    return true;
+  }
+
 
 
   public void