Several background pattern fixes on the Mac....

chrome/browser/cocoa/background_gradient_view_unittest.mm

 // Copyright (c) 2009 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #import <Cocoa/Cocoa.h>
 
 #include "base/scoped_nsobject.h"
 #import "chrome/browser/cocoa/background_gradient_view.h"
 #import "chrome/browser/cocoa/cocoa_test_helper.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "testing/platform_test.h"
 
+// Since BackgroundGradientView doesn't do any drawing by default, we
+// create a subclass to call its draw method for us.
+@interface BackgroundGradientSubClassTest : BackgroundGradientView
+@end
+
+@implementation BackgroundGradientSubClassTest
+- (void)drawRect:(NSRect)rect {
+  [self drawBackground];
+}
+@end
+
 namespace {
 
 class BackgroundGradientViewTest : public PlatformTest {
  public:
   BackgroundGradientViewTest() {
     NSRect frame = NSMakeRect(0, 0, 100, 30);
-    view_.reset([[BackgroundGradientView alloc] initWithFrame:frame]);
+    view_.reset([[BackgroundGradientSubClassTest alloc] initWithFrame:frame]);
     [cocoa_helper_.contentView() addSubview:view_.get()];
   }
 
   CocoaTestHelper cocoa_helper_;  // Inits Cocoa, creates window, etc...
-  scoped_nsobject<BackgroundGradientView> view_;
+  scoped_nsobject<BackgroundGradientSubClassTest> view_;
 };
 
 // Test adding/removing from the view hierarchy, mostly to ensure nothing
 // leaks or crashes.
 TEST_F(BackgroundGradientViewTest, AddRemove) {
   EXPECT_EQ(cocoa_helper_.contentView(), [view_ superview]);
   [view_.get() removeFromSuperview];
   EXPECT_FALSE([view_ superview]);
 }
 
 // Test drawing, mostly to ensure nothing leaks or crashes.
 TEST_F(BackgroundGradientViewTest, Display) {
   [view_ display];
   [view_ setShowsDivider:YES];
   [view_ display];
 }
 
 }  // namespace