Skip flushes on icon writes for 10x better jumplist perf

ui/gfx/icon_util.h

Index: ui/gfx/icon_util.h
diff --git a/ui/gfx/icon_util.h b/ui/gfx/icon_util.h
index a3dc30da6316d3ca8c8fce55e5a6118b91ad3aa2..1a48304735043801cb9b82f96dbb10dd49c8b50c 100644
--- a/ui/gfx/icon_util.h
+++ b/ui/gfx/icon_util.h
@@ -58,6 +58,11 @@ class SkBitmap;
 ///////////////////////////////////////////////////////////////////////////////
 class GFX_EXPORT IconUtil {
  public:
+  // ATOMIC_WRITE ensures that a partially written icon won't be created even if
+  // Chrome crashes part way through, but ATOMIC_WRITE is more expensive than
+  // NORMAL_WRITE. See CreateIconFileFromImageFamily. ATOMIC_WRITE is the
+  // default for historical reasons.
+  enum WriteType { ATOMIC_WRITE, NORMAL_WRITE };
   // The size of the large icon entries in .ico files on Windows Vista+.
   static const int kLargeIconSize = 256;
   // The size of icons in the medium icons view on Windows Vista+. This is the
@@ -126,7 +131,8 @@ class GFX_EXPORT IconUtil {
   // |image_family| is empty.
   static bool CreateIconFileFromImageFamily(
       const gfx::ImageFamily& image_family,
-      const base::FilePath& icon_path);
+      const base::FilePath& icon_path,
+      WriteType write_type = ATOMIC_WRITE);
 
   // Creates a cursor of the specified size from the DIB passed in.
   // Returns the cursor on success or NULL on failure.
@@ -139,7 +145,7 @@ class GFX_EXPORT IconUtil {
   // The icon format is published in the MSDN but there is no definition of
   // the icon file structures in any of the Windows header files so we need to
   // define these structure within the class. We must make sure we use 2 byte
-  // packing so that the structures are layed out properly within the file.
+  // packing so that the structures are laid out properly within the file.
   // See: http://msdn.microsoft.com/en-us/library/ms997538.aspx
 #pragma pack(push)
 #pragma pack(2)