AI 143728: Fix # 1743137: Suggestion bubble doesn't go away after empty space...

AI 143728: Fix # 1743137: Suggestion bubble doesn't go away after empty space on right end of suggestion strip is tapped.
  The empty space on right end sometimes registers as the word at the left end. Fixed this by checking for -1.
  Also fixed a bug where the strip moves in the wrong direction on drag, when it shouldn't move at all.
  BUG=1743137

Automated import of CL 143728

src/com/android/inputmethod/latin/CandidateView.java

@@ -148,16 +148,17 @@ public class CandidateView extends View {
             @Override
             public boolean onScroll(MotionEvent e1, MotionEvent e2,
                     float distanceX, float distanceY) {
+                final int width = getWidth();
                 mScrolled = true;
-                mScrollX += distanceX;
+                mScrollX += (int) distanceX;
                 if (mScrollX < 0) {
                     mScrollX = 0;
                 }
-                if (mScrollX + getWidth() > mTotalWidth) {                    
-                    mScrollX -= distanceX;
+                if (distanceX > 0 && mScrollX + width > mTotalWidth) {                    
+                    mScrollX -= (int) distanceX;
                 }
                 mTargetScrollX = mScrollX;
-                showPreview(OUT_OF_BOUNDS, null);
+                hidePreview();
                 invalidate();
                 return true;
             }
@@ -236,7 +237,8 @@ public class CandidateView extends View {
 
             mWordX[i] = x;
 
-            if (touchX + scrollX >= x && touchX + scrollX < x + wordWidth && !scrolled) {
+            if (touchX + scrollX >= x && touchX + scrollX < x + wordWidth && !scrolled &&
+                    touchX != OUT_OF_BOUNDS) {
                 if (canvas != null) {
                     canvas.translate(x, 0);
                     mSelectionHighlight.setBounds(0, bgPadding.top, wordWidth, height);
@@ -399,7 +401,7 @@ public class CandidateView extends View {
             mSelectedString = null;
             mSelectedIndex = -1;
             removeHighlight();
-            showPreview(OUT_OF_BOUNDS, null);
+            hidePreview();
             requestLayout();
             break;
         }
@@ -425,16 +427,21 @@ public class CandidateView extends View {
         mHandler.sendMessageDelayed(mHandler.obtainMessage(MSG_REMOVE_THROUGH_PREVIEW), 200);
     }
 
+    private void hidePreview() {
+        mCurrentWordIndex = OUT_OF_BOUNDS;
+        if (mPreviewPopup.isShowing()) {
+            mHandler.sendMessageDelayed(mHandler
+                    .obtainMessage(MSG_REMOVE_PREVIEW), 60);
+        }
+    }
+    
     private void showPreview(int wordIndex, String altText) {
         int oldWordIndex = mCurrentWordIndex;
         mCurrentWordIndex = wordIndex;
         // If index changed or changing text
         if (oldWordIndex != mCurrentWordIndex || altText != null) {
             if (wordIndex == OUT_OF_BOUNDS) {
-                if (mPreviewPopup.isShowing()) {
-                    mHandler.sendMessageDelayed(mHandler
-                            .obtainMessage(MSG_REMOVE_PREVIEW), 60);
-                }
+                hidePreview();
             } else {
                 CharSequence word = altText != null? altText : mSuggestions.get(wordIndex);
                 mPreviewText.setText(word);
@@ -475,4 +482,10 @@ public class CandidateView extends View {
             showPreview(0, getContext().getResources().getString(R.string.added_word, word));
         }
     }
+    
+    @Override
+    public void onDetachedFromWindow() {
+        super.onDetachedFromWindow();
+        hidePreview();
+    }
 }