Fix triggering logic for BottomSheet's onSheetOpened

This patch fixes some broken assumptions with the triggering logic for
onSheetOpened and onSheetClosed. Now the checks for the current state
explicitly check if the state is considered opened or closed.

Change-Id: I86be48e93450074ed5171a9d1919dc973451d20b
Reviewed-on: https://chromium-review.googlesource.com/998519Reviewed-by: Theresa <twellington@chromium.org>
Commit-Queue: Theresa <twellington@chromium.org>
Cr-Commit-Position: refs/heads/master@{#549198}

chrome/android/java/src/org/chromium/chrome/browser/widget/bottomsheet/BottomSheet.java

@@ -1258,6 +1258,8 @@ public class BottomSheet extends FrameLayout
             return;
         }
 
+        @SheetState
+        final int previousState = mCurrentState;
         mCurrentState = state;
 
         if (mCurrentState == SHEET_STATE_HALF || mCurrentState == SHEET_STATE_FULL) {
@@ -1280,13 +1282,31 @@ public class BottomSheet extends FrameLayout
             o.onSheetStateChanged(mCurrentState);
         }
 
-        if (state <= SHEET_STATE_PEEK) {
+        if (isSheetOpen() && isClosedState(getSheetState())) {
             onSheetClosed(reason);
-        } else {
+        } else if (!isSheetOpen() && isClosedState(previousState)
+                && isOpenedState(getSheetState())) {
             onSheetOpened(reason);
         }
     }
 
+    /**
+     * @param state A state of the {@link BottomSheet}.
+     * @return Whether the provided state is considered open.
+     */
+    private boolean isOpenedState(@SheetState int state) {
+        return state == SHEET_STATE_HALF || state == SHEET_STATE_FULL
+                || state == SHEET_STATE_SCROLLING;
+    }
+
+    /**
+     * @param state A state of the {@link BottomSheet}.
+     * @return Whether the provided state is considered closed.
+     */
+    private boolean isClosedState(@SheetState int state) {
+        return state == SHEET_STATE_PEEK || state == SHEET_STATE_HIDDEN;
+    }
+
     /**
      * If the animation to settle the sheet in one of its states is running.
      * @return True if the animation is running.