Program: 191059
Project: 191059
Buggy source:
/** 
 * Returns stack's visibility:   {@link #STACK_INVISIBLE},   {@link #STACK_VISIBLE} or{@link #STACK_VISIBLE_ACTIVITY_BEHIND}.
 * @param starting The currently starting activity or null if there is none.
 */
int getStackVisibilityLocked(ActivityRecord starting){
  if (!isAttached()) {
    return STACK_INVISIBLE;
  }
  if (mStackSupervisor.isFrontStack(this) || mStackSupervisor.isFocusedStack(this)) {
    return STACK_VISIBLE;
  }
  final int stackIndex=mStacks.indexOf(this);
  if (stackIndex == mStacks.size() - 1) {
    Slog.wtf(TAG,"String_Node_Str" + this + "String_Node_Str");
    return STACK_INVISIBLE;
  }
  final boolean isLockscreenShown=mService.mLockScreenShown == LOCK_SCREEN_SHOWN;
  if (isLockscreenShown && !StackId.isAllowedOverLockscreen(mStackId)) {
    return STACK_INVISIBLE;
  }
  final ActivityStack focusedStack=mStackSupervisor.getFocusedStack();
  final int focusedStackId=focusedStack.mStackId;
  if (mStackId == FULLSCREEN_WORKSPACE_STACK_ID && hasVisibleBehindActivity() && focusedStackId == HOME_STACK_ID && !focusedStack.topActivity().fullscreen) {
    return STACK_VISIBLE_ACTIVITY_BEHIND;
  }
  if (mStackId == DOCKED_STACK_ID) {
    final ActivityRecord r=focusedStack.topRunningActivityLocked();
    final TaskRecord task=r != null ? r.task : null;
    return task == null || task.canGoInDockedStack() || task.isHomeTask() ? STACK_VISIBLE : STACK_INVISIBLE;
  }
  int stackBehindFocusedIndex=mStacks.indexOf(focusedStack) - 1;
  while (stackBehindFocusedIndex >= 0 && mStacks.get(stackBehindFocusedIndex).topRunningActivityLocked() == null) {
    stackBehindFocusedIndex--;
  }
  if ((focusedStackId == DOCKED_STACK_ID || focusedStackId == PINNED_STACK_ID) && stackIndex == stackBehindFocusedIndex) {
    return STACK_VISIBLE;
  }
  final int stackBehindFocusedId=(stackBehindFocusedIndex >= 0) ? mStacks.get(stackBehindFocusedIndex).mStackId : INVALID_STACK_ID;
  if (focusedStackId == FULLSCREEN_WORKSPACE_STACK_ID && focusedStack.isStackTranslucent(starting,stackBehindFocusedId)) {
    if (stackIndex == stackBehindFocusedIndex) {
      return STACK_VISIBLE;
    }
    if (stackBehindFocusedIndex >= 0) {
      if ((stackBehindFocusedId == DOCKED_STACK_ID || stackBehindFocusedId == PINNED_STACK_ID) && stackIndex == (stackBehindFocusedIndex - 1)) {
        return STACK_VISIBLE;
      }
    }
  }
  if (StackId.isStaticStack(mStackId)) {
    return STACK_INVISIBLE;
  }
  for (int i=stackIndex + 1; i < mStacks.size(); i++) {
    final ActivityStack stack=mStacks.get(i);
    if (!stack.mFullscreen && !stack.hasFullscreenTask()) {
      continue;
    }
    if (!StackId.isDynamicStacksVisibleBehindAllowed(stack.mStackId)) {
      return STACK_INVISIBLE;
    }
    if (!stack.isStackTranslucent(starting,INVALID_STACK_ID)) {
      return STACK_INVISIBLE;
    }
  }
  return STACK_VISIBLE;
}

Fixed version (ground truth):
/** 
 * Returns stack's visibility:   {@link #STACK_INVISIBLE},   {@link #STACK_VISIBLE} or{@link #STACK_VISIBLE_ACTIVITY_BEHIND}.
 * @param starting The currently starting activity or null if there is none.
 */
int getStackVisibilityLocked(ActivityRecord starting){
  if (!isAttached()) {
    return STACK_INVISIBLE;
  }
  if (mStackSupervisor.isFrontStack(this) || mStackSupervisor.isFocusedStack(this)) {
    return STACK_VISIBLE;
  }
  final int stackIndex=mStacks.indexOf(this);
  if (stackIndex == mStacks.size() - 1) {
    Slog.wtf(TAG,"String_Node_Str" + this + "String_Node_Str");
    return STACK_INVISIBLE;
  }
  final ActivityStack focusedStack=mStackSupervisor.getFocusedStack();
  final int focusedStackId=focusedStack.mStackId;
  if (mStackId == FULLSCREEN_WORKSPACE_STACK_ID && hasVisibleBehindActivity() && focusedStackId == HOME_STACK_ID && !focusedStack.topActivity().fullscreen) {
    return STACK_VISIBLE_ACTIVITY_BEHIND;
  }
  if (mStackId == DOCKED_STACK_ID) {
    final ActivityRecord r=focusedStack.topRunningActivityLocked();
    final TaskRecord task=r != null ? r.task : null;
    return task == null || task.canGoInDockedStack() || task.isHomeTask() ? STACK_VISIBLE : STACK_INVISIBLE;
  }
  int stackBehindFocusedIndex=mStacks.indexOf(focusedStack) - 1;
  while (stackBehindFocusedIndex >= 0 && mStacks.get(stackBehindFocusedIndex).topRunningActivityLocked() == null) {
    stackBehindFocusedIndex--;
  }
  if ((focusedStackId == DOCKED_STACK_ID || focusedStackId == PINNED_STACK_ID) && stackIndex == stackBehindFocusedIndex) {
    return STACK_VISIBLE;
  }
  final int stackBehindFocusedId=(stackBehindFocusedIndex >= 0) ? mStacks.get(stackBehindFocusedIndex).mStackId : INVALID_STACK_ID;
  if (focusedStackId == FULLSCREEN_WORKSPACE_STACK_ID && focusedStack.isStackTranslucent(starting,stackBehindFocusedId)) {
    if (stackIndex == stackBehindFocusedIndex) {
      return STACK_VISIBLE;
    }
    if (stackBehindFocusedIndex >= 0) {
      if ((stackBehindFocusedId == DOCKED_STACK_ID || stackBehindFocusedId == PINNED_STACK_ID) && stackIndex == (stackBehindFocusedIndex - 1)) {
        return STACK_VISIBLE;
      }
    }
  }
  if (StackId.isStaticStack(mStackId)) {
    return STACK_INVISIBLE;
  }
  for (int i=stackIndex + 1; i < mStacks.size(); i++) {
    final ActivityStack stack=mStacks.get(i);
    if (!stack.mFullscreen && !stack.hasFullscreenTask()) {
      continue;
    }
    if (!StackId.isDynamicStacksVisibleBehindAllowed(stack.mStackId)) {
      return STACK_INVISIBLE;
    }
    if (!stack.isStackTranslucent(starting,INVALID_STACK_ID)) {
      return STACK_INVISIBLE;
    }
  }
  return STACK_VISIBLE;
}