Fixed SpellCheckerSessions leak in TextView

Bug 5709546

Change 1a22db2 created a potential leak: setText calls
sendOnTextChange that now calls updateSpellCheckSpans.

The original call to updateSpellCheckSpans made sure the
View had been attached to a window, through the existence
of the SpellChecker object.

The mSpellChecker object will now only be created when the
View is attached, all other spell related method will do
nothing if it has not been initialized.

Change-Id: I8885c12be6395e2346c0ed057bb6a275256f012b

Author: Gilles Debunne

core/java/android/widget/TextView.java

@@ -3207,7 +3207,6 @@ private void setText(CharSequence text, BufferType type,
         }
 
         boolean needEditableForNotification = false;
-        boolean startSpellCheck = false;
 
         if (mListeners != null && mListeners.size() != 0) {
             needEditableForNotification = true;
@@ -3219,7 +3218,6 @@ private void setText(CharSequence text, BufferType type,
             setFilters(t, mFilters);
             InputMethodManager imm = InputMethodManager.peekInstance();
             if (imm != null) imm.restartInput(this);
-            startSpellCheck = true;
         } else if (type == BufferType.SPANNABLE || mMovement != null) {
             text = mSpannableFactory.newSpannable(text);
         } else if (!(text instanceof CharWrapper)) {
@@ -3308,11 +3306,6 @@ private void setText(CharSequence text, BufferType type,
         sendOnTextChanged(text, 0, oldlen, textLength);
         onTextChanged(text, 0, oldlen, textLength);
 
-        if (startSpellCheck && mSpellChecker != null) {
-            // This view has to have been previously attached for mSpellChecker to exist  
-            updateSpellCheckSpans(0, textLength);
-        }
-
         if (needEditableForNotification) {
             sendAfterTextChanged((Editable) text);
         }
@@ -4479,8 +4472,8 @@ protected void onAttachedToWindow() {
 
         // Resolve drawables as the layout direction has been resolved
         resolveDrawables();
-        
-        updateSpellCheckSpans(0, mText.length());
+
+        updateSpellCheckSpans(0, mText.length(), true /* create the spell checker if needed */);
     }
 
     @Override
@@ -7631,7 +7624,7 @@ void sendOnTextChanged(CharSequence text, int start, int before, int after) {
             }
         }
 
-        updateSpellCheckSpans(start, start + after);
+        updateSpellCheckSpans(start, start + after, false);
 
         // Hide the controllers as soon as text is modified (typing, procedural...)
         // We do not hide the span controllers, since they can be added when a new text is
@@ -7789,17 +7782,22 @@ void spanChange(Spanned buf, Object what, int oldStart, int newStart, int oldEnd
             }
         }
 
-        if (newStart < 0 && what instanceof SpellCheckSpan) {
-            getSpellChecker().removeSpellCheckSpan((SpellCheckSpan) what);
+        if (mSpellChecker != null && newStart < 0 && what instanceof SpellCheckSpan) {
+            mSpellChecker.removeSpellCheckSpan((SpellCheckSpan) what);
         }
     }
 
     /**
      * Create new SpellCheckSpans on the modified region.
      */
-    private void updateSpellCheckSpans(int start, int end) {
+    private void updateSpellCheckSpans(int start, int end, boolean createSpellChecker) {
         if (isTextEditable() && isSuggestionsEnabled()) {
-            getSpellChecker().spellCheck(start, end);
+            if (mSpellChecker == null && createSpellChecker) {
+                mSpellChecker = new SpellChecker(this);
+            }
+            if (mSpellChecker != null) {
+                mSpellChecker.spellCheck(start, end);
+            }
         }
     }
 
@@ -8970,13 +8968,6 @@ private long getCharRange(int offset) {
         return packRangeInLong(offset,  offset);
     }
 
-    private SpellChecker getSpellChecker() {
-        if (mSpellChecker == null) {
-            mSpellChecker = new SpellChecker(this);
-        }
-        return mSpellChecker;
-    }
-
     private long getLastTouchOffsets() {
         SelectionModifierCursorController selectionController = getSelectionController();
         final int minOffset = selectionController.getMinTouchOffset();
@@ -9930,7 +9921,7 @@ public void onItemClick(AdapterView<?> parent, View view, int position, long id)
                 // There is no way to know if the word was indeed added. Re-check.
                 // TODO The ExtractEditText should remove the span in the original text instead
                 editable.removeSpan(suggestionInfo.suggestionSpan);
-                updateSpellCheckSpans(spanStart, spanEnd);
+                updateSpellCheckSpans(spanStart, spanEnd, false);
             } else {
                 // SuggestionSpans are removed by replace: save them before
                 SuggestionSpan[] suggestionSpans = editable.getSpans(spanStart, spanEnd,