Support detaching/attaching panels via inter-strip drags.

chrome/browser/ui/panels/panel_window_controller_cocoa.mm

Index: chrome/browser/ui/panels/panel_window_controller_cocoa.mm
diff --git a/chrome/browser/ui/panels/panel_window_controller_cocoa.mm b/chrome/browser/ui/panels/panel_window_controller_cocoa.mm
index 5ce263b6cdcc58c6439651ae6f79399caba4bc23..2d883bc3b97e68610c06647eee17093d634aef8e 100644
--- a/chrome/browser/ui/panels/panel_window_controller_cocoa.mm
+++ b/chrome/browser/ui/panels/panel_window_controller_cocoa.mm
@@ -58,6 +58,20 @@ enum {
 
 #endif  // MAC_OS_X_VERSION_10_6
 
+namespace {
+
+// Converts a point from the Cocoa screen coordinates (with (0,0) in the
+// low-left corner of the primary screen) to the platfrom-independent screen
+// coordinates (with the (0,0) in the top-left corner).
+gfx::Point ConvertPointFromCocoaCoordinates(NSPoint point) {
+  // Flip coordinates based on the primary screen.
+  NSScreen* screen = [[NSScreen screens] objectAtIndex:0];
+
+  return gfx::Point(point.x, NSHeight([screen frame]) - point.y);
+}
+
+}  // namespace
+
 @implementation PanelWindowCocoaImpl
 - (NSRect)constrainFrameRect:(NSRect)frameRect toScreen:(NSScreen *)screen {
   return frameRect;
@@ -402,9 +416,10 @@ enum {
   return windowShim_->panel()->draggable();
 }
 
-- (void)startDrag {
+- (void)startDrag:(NSPoint)mouseLocation {
   animateOnBoundsChange_ = NO;
-  windowShim_->panel()->manager()->StartDragging(windowShim_->panel());
+  windowShim_->panel()->manager()->StartDragging(
+      windowShim_->panel(), ConvertPointFromCocoaCoordinates(mouseLocation));
 }
 
 - (void)endDrag:(BOOL)cancelled {
@@ -412,9 +427,9 @@ enum {
   windowShim_->panel()->manager()->EndDragging(cancelled);
 }
 
-- (void)dragWithDeltaX:(int)deltaX
-                deltaY:(int)deltaY {
-  windowShim_->panel()->manager()->Drag(deltaX, deltaY);
+- (void)drag:(NSPoint)mouseLocation {
+  windowShim_->panel()->manager()->Drag(
+      ConvertPointFromCocoaCoordinates(mouseLocation));
 }
 
 - (void)setPanelFrame:(NSRect)frame
@@ -624,4 +639,9 @@ enum {
   // cases when minimized Panel is getting keyboard input, invisibly.
   return windowShim_->panel()->expansion_state() == Panel::EXPANDED;
 }
+
+- (void)setAlwaysOnTop:(bool)onTop {
+  NSWindow* window = [self window];
+  [window setLevel:(onTop ? NSStatusWindowLevel : NSNormalWindowLevel)];
+}
 @end