Add "dangerous download" view on OS X, for now for dmg files. Also fix download item layout.

chrome/browser/cocoa/download_item_controller.h

Index: chrome/browser/cocoa/download_item_controller.h
diff --git a/chrome/browser/cocoa/download_item_controller.h b/chrome/browser/cocoa/download_item_controller.h
index 04b28d56657f0fc36a462c1d900d3d94fd663754..dd8d4e2c738853af4eae18d79e9e54059490168c 100644
--- a/chrome/browser/cocoa/download_item_controller.h
+++ b/chrome/browser/cocoa/download_item_controller.h
@@ -5,6 +5,7 @@
 #import <Cocoa/Cocoa.h>
 
 #include "base/scoped_ptr.h"
+#include "base/time.h"
 
 class BaseDownloadItemModel;
 @class DownloadItemCell;
@@ -24,16 +25,28 @@ class DownloadShelfContextMenuMac;
 
   NSMenu* currentMenu_;  // points to one of the two menus above
 
+  // This is shown instead of progressView_ for dangerous downloads.
+  IBOutlet NSView* dangerousDownloadView_;
+  IBOutlet NSTextField* dangerousDownloadLabel_;
+
   scoped_ptr<DownloadItemMac> bridge_;
   scoped_ptr<DownloadShelfContextMenuMac> menuBridge_;
 
   // Weak pointer to the shelf that owns us.
   DownloadShelfController* shelf_;
+  
+  // The time at which this view was created.
+  base::Time creationTime_;
+
+  // The state of this item.
+  enum DownoadItemState {
+    kNormal,
+    kDangerous
+  } state_;
 };
 
 // Takes ownership of |downloadModel|.
-- (id)initWithFrame:(NSRect)frameRect
-              model:(BaseDownloadItemModel*)downloadModel
+- (id)initWithModel:(BaseDownloadItemModel*)downloadModel
               shelf:(DownloadShelfController*)shelf;
 
 // Updates the UI and menu state from |downloadModel|.
@@ -52,6 +65,15 @@ class DownloadShelfContextMenuMac;
 // Download item button clicked
 - (IBAction)handleButtonClick:(id)sender;
 
+// Returns the size this item wants to have.
+- (NSSize)preferredSize;
+
+// Handling of dangerous downloads
+- (void)clearDangerousMode;
+- (BOOL)isDangerousMode;
+- (IBAction)saveDownload:(id)sender;
+- (IBAction)discardDownload:(id)sender;
+
 // Context menu handlers.
 - (IBAction)handleOpen:(id)sender;
 - (IBAction)handleAlwaysOpen:(id)sender;