Use visibleFrame to calculate scrolling vector

Summary:
Using views frame for calculating scroling vector might be buggy when application is doing tricky stuff with scolling views eg. nesting scrollview within scrollview.
In that case frame of the second scrollview will be huge and make scrolling imposible as we will try to use points of the screen. Instead we should visible frame.

Reviewed By: antiarchit

Differential Revision: D6819626

fbshipit-source-id: 27062f593485b4ec55ae8bd1a9c9a32a89630b92

WebDriverAgentLib/Categories/XCUIElement+FBScrolling.m

@@ -204,6 +204,11 @@ - (BOOL)fb_isEquivalentElementSnapshotVisible:(XCElementSnapshot *)snapshot
 
 @implementation XCElementSnapshot (FBScrolling)
 
+- (CGRect)scrollingFrame
+{
+  return self.visibleFrame;
+}
+
 - (void)fb_scrollUpByNormalizedDistance:(CGFloat)distance inApplication:(XCUIApplication *)application
 {
   [self fb_scrollByNormalizedVector:CGVectorMake(0.0, distance) inApplication:application];
@@ -226,16 +231,16 @@ - (void)fb_scrollRightByNormalizedDistance:(CGFloat)distance inApplication:(XCUI
 
 - (BOOL)fb_scrollByNormalizedVector:(CGVector)normalizedScrollVector inApplication:(XCUIApplication *)application
 {
-  CGVector scrollVector = CGVectorMake(CGRectGetWidth(self.frame) * normalizedScrollVector.dx,
-                                       CGRectGetHeight(self.frame) * normalizedScrollVector.dy
+  CGVector scrollVector = CGVectorMake(CGRectGetWidth(self.scrollingFrame) * normalizedScrollVector.dx,
+                                       CGRectGetHeight(self.scrollingFrame) * normalizedScrollVector.dy
                                        );
   return [self fb_scrollByVector:scrollVector inApplication:application error:nil];
 }
 
 - (BOOL)fb_scrollByVector:(CGVector)vector inApplication:(XCUIApplication *)application error:(NSError **)error
 {
-  CGVector scrollBoundingVector = CGVectorMake(CGRectGetWidth(self.frame) * FBScrollTouchProportion - FBScrollBoundingVelocityPadding,
-                                               CGRectGetHeight(self.frame)* FBScrollTouchProportion - FBScrollBoundingVelocityPadding
+  CGVector scrollBoundingVector = CGVectorMake(CGRectGetWidth(self.scrollingFrame) * FBScrollTouchProportion - FBScrollBoundingVelocityPadding,
+                                               CGRectGetHeight(self.scrollingFrame)* FBScrollTouchProportion - FBScrollBoundingVelocityPadding
                                                );
   scrollBoundingVector.dx = (CGFloat)floor(copysign(scrollBoundingVector.dx, vector.dx));
   scrollBoundingVector.dy = (CGFloat)floor(copysign(scrollBoundingVector.dy, vector.dy));
@@ -257,8 +262,8 @@ - (BOOL)fb_scrollByVector:(CGVector)vector inApplication:(XCUIApplication *)appl
 
 - (CGVector)fb_hitPointOffsetForScrollingVector:(CGVector)scrollingVector
 {
-  CGFloat x = CGRectGetMinX(self.frame) + CGRectGetWidth(self.frame) * (scrollingVector.dx < 0.0f ? FBScrollTouchProportion : (1 - FBScrollTouchProportion));
-  CGFloat y = CGRectGetMinY(self.frame) + CGRectGetHeight(self.frame) * (scrollingVector.dy < 0.0f ? FBScrollTouchProportion : (1 - FBScrollTouchProportion));
+  CGFloat x = CGRectGetMinX(self.scrollingFrame) + CGRectGetWidth(self.scrollingFrame) * (scrollingVector.dx < 0.0f ? FBScrollTouchProportion : (1 - FBScrollTouchProportion));
+  CGFloat y = CGRectGetMinY(self.scrollingFrame) + CGRectGetHeight(self.scrollingFrame) * (scrollingVector.dy < 0.0f ? FBScrollTouchProportion : (1 - FBScrollTouchProportion));
   return CGVectorMake((CGFloat)floor(x), (CGFloat)floor(y));
 }