[Toolbar Mac UI] Simplify and correct omnibox pinning

chrome/browser/ui/cocoa/extensions/browser_actions_container_view.mm

Index: chrome/browser/ui/cocoa/extensions/browser_actions_container_view.mm
diff --git a/chrome/browser/ui/cocoa/extensions/browser_actions_container_view.mm b/chrome/browser/ui/cocoa/extensions/browser_actions_container_view.mm
index d5338ae104002e17c74bbdeeba14882bdb28d35b..ecd68752398300c86fdc5f14fdc5650bf067c349 100644
--- a/chrome/browser/ui/cocoa/extensions/browser_actions_container_view.mm
+++ b/chrome/browser/ui/cocoa/extensions/browser_actions_container_view.mm
@@ -120,7 +120,6 @@ const CGFloat kMinimumContainerWidth = 3.0;
       !NSMouseInRect(initialDragPoint_, grippyRect_, [self isFlipped]))
     return;
 
-  lastXPos_ = [self frame].origin.x;
   userIsResizing_ = YES;
 
   [[self appropriateCursorForGrippy] push];
@@ -180,8 +179,6 @@ const CGFloat kMinimumContainerWidth = 3.0;
   [[NSNotificationCenter defaultCenter]
       postNotificationName:kBrowserActionGrippyDraggingNotification
                     object:self];
-
-  lastXPos_ += dX;
 }
 
 - (ViewID)viewID {
@@ -198,7 +195,6 @@ const CGFloat kMinimumContainerWidth = 3.0;
   CGFloat maxAllowedWidth = [self maxAllowedWidth];
   width = std::min(maxAllowedWidth, width);
 
-  lastXPos_ = frame.origin.x;
   CGFloat dX = frame.size.width - width;
   frame.size.width = width;
   NSRect newFrame = NSOffsetRect(frame, dX, 0);
@@ -225,10 +221,6 @@ const CGFloat kMinimumContainerWidth = 3.0;
   }
 }
 
-- (CGFloat)resizeDeltaX {
-  return [self frame].origin.x - lastXPos_;
-}
-
 - (NSRect)animationEndFrame {
   if ([resizeAnimation_ isAnimating]) {
     NSRect endFrame = [[[[resizeAnimation_ viewAnimations] objectAtIndex:0]