Bug 1721395 - Don't send composing text to Gecko when selection is out of composing range. r=geckoview-reviewers,agi

Actually, Gecko cannot set caret position that is out of composing range. When
having composition, caret (in other word, IME caret) has to be within composing
string.

But Android's text framework can set caret position (selection) that is out of
composing range. Example, Android can have the following. `"ABCD[]"` is current
text and `[]` is selection and AB is composing string. But Gecko cannot.

So if this situation, we have to remove composing state then set selection from
Android's.

Differential Revision: https://phabricator.services.mozilla.com/D121502

mobile/android/geckoview/src/main/java/org/mozilla/geckoview/GeckoEditable.java

@@ -819,12 +819,26 @@ import android.view.inputmethod.EditorInfo;
             }
 
             if (found) {
-                icSendComposition(text, selStart, selEnd, composingStart, composingEnd);
-                if (notifyGecko) {
-                    mFocusedChild.onImeUpdateComposition(
-                            composingStart, composingEnd, updateFlags);
+                if (selStart < composingStart || selEnd > composingEnd) {
+                    // GBoard will set caret position that is out of composing
+                    // range. Unfortunately, Gecko doesn't support this caret
+                    // position. So we shouldn't set composing range data now.
+                    // But this is temporary composing range, then GBoard will
+                    // set valid range soon.
+                    if (DEBUG) {
+                        final StringBuilder sb = new StringBuilder("icSendComposition(): invalid caret position. ");
+                        sb.append("composing = ").append(composingStart).append("-").append(composingEnd)
+                          .append(", selection = ").append(selStart).append("-").append(selEnd);
+                        Log.d(LOGTAG, sb.toString());
+                    }
+                } else {
+                    icSendComposition(text, selStart, selEnd, composingStart, composingEnd);
+                    if (notifyGecko) {
+                        mFocusedChild.onImeUpdateComposition(
+                                composingStart, composingEnd, updateFlags);
+                    }
+                    return true;
                 }
-                return true;
             }
         }
 
@@ -855,12 +869,11 @@ import android.view.inputmethod.EditorInfo;
             throws RemoteException {
         if (DEBUG) {
             assertOnIcThread();
-            Log.d(LOGTAG, "icSendComposition(\"" + text + "\", " +
-                                             composingStart + ", " + composingEnd + ")");
-        }
-        if (DEBUG) {
-            Log.d(LOGTAG, " range = " + composingStart + "-" + composingEnd);
-            Log.d(LOGTAG, " selection = " + selStart + "-" + selEnd);
+            final StringBuilder sb = new StringBuilder("icSendComposition(");
+            sb.append("\"").append(text).append("\"")
+              .append(", range = ").append(composingStart).append("-").append(composingEnd)
+              .append(", selection = ").append(selStart).append("-").append(selEnd).append(")");
+            Log.d(LOGTAG, sb.toString());
         }
 
         if (selEnd >= composingStart && selEnd <= composingEnd) {