Revert of BackgroundGradientView: -drawBackground: → -drawRect: (patchset #2...

Revert of BackgroundGradientView: -drawBackground: → -drawRect: (patchset #2 id:40001 of https://codereview.chromium.org/2336453002/ )

Reason for revert:
AnimatableView inherits from BackgroundGradientView, so a number of
other views which *don't* want backgrounds end up inheriting from
BackgroundGradientView. This widened the scope of the change beyond what
I intended.

Original issue's description:
> BackgroundGradientView: -drawBackground: → -drawRect:
>
> BackgroundGradientView had a -drawBackground: method that its clients
> were expected to call. This change moves background drawing to
> -drawRect: so that the it happens by default.
>
> Subclasses that did custom drawing already override -drawRect:, but this
> removes a couple of overrides that just forwarded to -drawBackground:.
>
> BUG=589943
>
> Committed: https://crrev.com/6b1939a26d2839136aeeba2aa0e359fce0c20281
> Cr-Commit-Position: refs/heads/master@{#418358}

TBR=thakis@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=647018

Review-Url: https://codereview.chromium.org/2339143003
Cr-Commit-Position: refs/heads/master@{#418714}

chrome/browser/ui/cocoa/background_gradient_view.h

@@ -22,12 +22,15 @@
 // The color used for the bottom stroke. Public so subclasses can use.
 - (NSColor*)strokeColor;
 
-// The pattern phase that will be used by -drawRect:.
+// The pattern phase that will be used by -drawBackground:.
 // Defaults to align the top of the theme image with the top of the tabs.
 // Views that draw at the bottom of the window (download bar) can override to
 // change the pattern phase.
 - (NSPoint)patternPhase;
 
+// Draws the background image into the current NSGraphicsContext.
+- (void)drawBackground:(NSRect)dirtyRect;
+
 @end
 
 #endif  // CHROME_BROWSER_UI_COCOA_BACKGROUND_GRADIENT_VIEW_H_

chrome/browser/ui/cocoa/background_gradient_view.mm

@@ -55,7 +55,7 @@
       themeImagePositionForAlignment:THEME_IMAGE_ALIGN_WITH_TAB_STRIP];
 }
 
-- (void)drawRect:(NSRect)dirtyRect {
+- (void)drawBackground:(NSRect)dirtyRect {
   [[NSGraphicsContext currentContext]
       cr_setPatternPhase:[self patternPhase]
                  forView:[self cr_viewBeingDrawnTo]];

chrome/browser/ui/cocoa/background_gradient_view_unittest.mm

@@ -10,19 +10,32 @@
 #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)dirtyRect {
+  [self drawBackground:dirtyRect];
+}
+
+@end
+
 namespace {
 
 class BackgroundGradientViewTest : public CocoaTest {
  public:
   BackgroundGradientViewTest() {
     NSRect frame = NSMakeRect(0, 0, 100, 30);
-    base::scoped_nsobject<BackgroundGradientView> view(
-        [[BackgroundGradientView alloc] initWithFrame:frame]);
+    base::scoped_nsobject<BackgroundGradientSubClassTest> view(
+        [[BackgroundGradientSubClassTest alloc] initWithFrame:frame]);
     view_ = view.get();
     [[test_window() contentView] addSubview:view_];
   }
 
-  BackgroundGradientView* view_;
+  BackgroundGradientSubClassTest* view_;
 };
 
 TEST_VIEW(BackgroundGradientViewTest, view_)

chrome/browser/ui/cocoa/bookmarks/bookmark_bar_toolbar_view.mm

@@ -24,8 +24,8 @@
 @implementation BookmarkBarToolbarView
 
 - (BOOL)isOpaque {
-  // -drawRect: calls -drawAsDetachedBubble: or -[super drawRect:], both of
-  // which fill the dirty rect with an opaque color.
+  // -drawRect: calls -drawAsDetachedBubble: or -drawBackground:, both of which
+  // fill the dirty rect with an opaque color.
   return YES;
 }
 
@@ -41,7 +41,7 @@
       [controller_ isAnimatingFromState:BookmarkBar::DETACHED]) {
     [self drawAsDetachedBubble:dirtyRect];
   } else {
-    [super drawRect:dirtyRect];
+    [self drawBackground:dirtyRect];
   }
 }
 
@@ -70,7 +70,7 @@
     CGContextRef cgContext = static_cast<CGContextRef>([context graphicsPort]);
     CGContextSetAlpha(cgContext, 1 - morph);
     CGContextBeginTransparencyLayer(cgContext, NULL);
-    [super drawRect:dirtyRect];
+    [self drawBackground:dirtyRect];
     CGContextEndTransparencyLayer(cgContext);
   }
 

chrome/browser/ui/cocoa/download/download_shelf_view_cocoa.mm

@@ -38,7 +38,7 @@
 }
 
 - (void)drawRect:(NSRect)dirtyRect {
-  [super drawRect:dirtyRect];
+  [self drawBackground:dirtyRect];
 
   // Draw the top highlight
   NSRect borderRect, contentRect;

chrome/browser/ui/cocoa/find_bar/find_bar_view_cocoa.mm

@@ -75,7 +75,7 @@ CGFloat kCurveSize = 8;
   {
     gfx::ScopedNSGraphicsContextSaveGState scopedGState;
     [path addClip];
-    [super drawRect:dirtyRect];
+    [self drawBackground:dirtyRect];
   }
 
   [[self strokeColor] set];

chrome/browser/ui/cocoa/tabs/tab_strip_view.mm

@@ -66,7 +66,7 @@
     NSRect backgroundRect = [self bounds];
     backgroundRect.size.height = 2 * [self cr_lineWidth];
     if (NSIntersectsRect(backgroundRect, dirtyRect))
-      [super drawRect:backgroundRect];
+      [self drawBackground:backgroundRect];
 
     // Draw the border bitmap, which is partially transparent.
     NSImage* image = themeProvider->GetNSImageNamed(IDR_TOOLBAR_SHADE_TOP);
@@ -90,7 +90,7 @@
     NSRect backgroundRect = [self bounds];
     backgroundRect.size.height = [self cr_lineWidth];
     if (NSIntersectsRect(backgroundRect, dirtyRect)) {
-      [super drawRect:backgroundRect];
+      [self drawBackground:backgroundRect];
     }
 
     // Pre-MD the IDR_TOOLBAR_SHADE_TOP image would lay down a light highlight

chrome/browser/ui/cocoa/toolbar/toolbar_view_cocoa.mm

@@ -17,6 +17,10 @@
   return NO;
 }
 
+- (void)drawRect:(NSRect)dirtyRect {
+  [self drawBackground:dirtyRect];
+}
+
 // Override of |-[BackgroundGradientView strokeColor]|; make it respect opacity.
 - (NSColor*)strokeColor {
   // Only return a transparent color if not Material Design.