Chore: Scroll drawing/highlight annotations into view on popover render (#360)

Author: pramodsum

src/doc/DocDrawingThread.js

@@ -192,13 +192,6 @@ class DocDrawingThread extends DrawingThread {
         this.draw(context, false);
     }
 
-    /**
-     * Do nothing for drawing annotations
-     *
-     * @return {void}
-     */
-    scrollIntoView() {}
-
     /** @inheritdoc */
     hide() {
         this.clearBoundary();

src/doc/DocHighlightThread.js

@@ -262,9 +262,15 @@ class DocHighlightThread extends AnnotationThread {
     /**
      * Scroll annotation into the center of the viewport, if possible
      *
+     * @param {number|null} dialogYPos - Y coordinate of the annotation popover
      * @return {void}
      */
-    scrollIntoView() {
+    scrollIntoView(dialogYPos: ?number) {
+        if (dialogYPos) {
+            super.scrollIntoView(dialogYPos);
+            return;
+        }
+
         this.scrollToPage();
 
         // $FlowFixMe
@@ -490,8 +496,10 @@ class DocHighlightThread extends AnnotationThread {
             dialogY = pageHeight - INLINE_POPOVER_HEIGHT;
         }
 
+        const dialogTopY = dialogY + INLINE_POPOVER_HEIGHT / 2 - BORDER_OFFSET;
         popoverEl.style.left = `${dialogX}px`;
-        popoverEl.style.top = `${dialogY + INLINE_POPOVER_HEIGHT / 2 - BORDER_OFFSET}px`;
+        popoverEl.style.top = `${dialogTopY}px`;
+        this.scrollIntoView(dialogTopY);
     };
 
     /** @inheritdoc */

src/doc/__tests__/DocHighlightThread-test.js

@@ -288,6 +288,21 @@ describe('doc/DocHighlightThread', () => {
         });
     });
 
+    describe('scrollIntoView()', () => {
+        beforeEach(() => {
+            thread.scrollToPage = jest.fn();
+            thread.centerAnnotation = jest.fn();
+            thread.annotatedElement.scrollTop = 0;
+            docUtil.getLowerRightCornerOfLastQuadPoint = jest.fn().mockReturnValue(20);
+        });
+
+        it('should call super.scrollIntoView() if dialog Y position was passed in as an argument', () => {
+            thread.scrollIntoView(10);
+            expect(docUtil.getLowerRightCornerOfLastQuadPoint).not.toBeCalled();
+            expect(thread.centerAnnotation).toBeCalledWith(10);
+        });
+    });
+
     describe('draw()', () => {
         it('should not draw if no context exists', () => {
             thread.getPageEl = jest.fn();