[Mac] Unspoofable infobars v3.

chrome/browser/ui/cocoa/infobars/infobar_gradient_view.mm

 // Copyright (c) 2011 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.
 
 #include "chrome/browser/ui/cocoa/infobars/infobar_gradient_view.h"
 
 #include "base/memory/scoped_nsobject.h"
 #include "chrome/browser/tab_contents/infobar.h"
 #import "chrome/browser/themes/theme_service.h"
+#import "chrome/browser/ui/cocoa/browser_window_controller.h"
 #import "chrome/browser/ui/cocoa/infobars/infobar_container_controller.h"
+#import "chrome/browser/ui/cocoa/location_bar/location_bar_view_mac.h"
 #import "chrome/browser/ui/cocoa/themed_window.h"
 #include "skia/ext/skia_utils_mac.h"
 
+namespace {
+
+const CGFloat kTipWidth = 23;
+
+}  // namespace
+
 @implementation InfoBarGradientView
 
+@synthesize tipApex = tipApex_;
+
 - (void)setInfobarType:(InfoBarDelegate::Type)infobarType {
   SkColor topColor = GetInfoBarTopColor(infobarType);
   SkColor bottomColor = GetInfoBarBottomColor(infobarType);
   scoped_nsobject<NSGradient> gradient([[NSGradient alloc]
       initWithStartingColor:gfx::SkColorToCalibratedNSColor(topColor)
                 endingColor:gfx::SkColorToCalibratedNSColor(bottomColor)]);
   [self setGradient:gradient];
 }
 
 - (NSColor*)strokeColor {
   ui::ThemeProvider* themeProvider = [[self window] themeProvider];
   if (!themeProvider)
     return [NSColor blackColor];
 
   BOOL active = [[self window] isMainWindow];
   return themeProvider->GetNSColor(
       active ? ThemeService::COLOR_TOOLBAR_STROKE :
                ThemeService::COLOR_TOOLBAR_STROKE_INACTIVE,
       true);
 }
 
 - (void)drawRect:(NSRect)rect {
   NSRect bounds = [self bounds];
   bounds.size.height = infobars::kBaseHeight;
 
+  const CGFloat kHalfWidth = kTipWidth / 2.0;
+  const CGFloat kTipXOffset = self.tipApex.x - kHalfWidth;
+
   // Around the bounds of the infobar, continue drawing the path into which the
   // gradient will be drawn.
   NSBezierPath* infoBarPath = [NSBezierPath bezierPath];
   [infoBarPath moveToPoint:NSMakePoint(NSMinX(bounds), NSMaxY(bounds))];
+
+  // Draw the tip.
+  [infoBarPath lineToPoint:NSMakePoint(kTipXOffset, NSMaxY(bounds))];
+  [infoBarPath relativeLineToPoint:NSMakePoint(kHalfWidth,
+                                               infobars::kTipHeight)];
+  [infoBarPath relativeLineToPoint:NSMakePoint(kHalfWidth,
+                                               -infobars::kTipHeight)];
   [infoBarPath lineToPoint:NSMakePoint(NSMaxX(bounds), NSMaxY(bounds))];
+
+  // Save off the top path of the infobar.
   scoped_nsobject<NSBezierPath> topPath([infoBarPath copy]);
 
   [infoBarPath lineToPoint:NSMakePoint(NSMaxX(bounds), NSMinY(bounds))];
   [infoBarPath lineToPoint:NSMakePoint(NSMinX(bounds), NSMinY(bounds))];
   [infoBarPath closePath];
 
   // Draw the gradient.
   [[self gradient] drawInBezierPath:infoBarPath angle:270];
 
-  // Stroke the bottom.
   NSColor* strokeColor = [self strokeColor];
   if (strokeColor) {
     [strokeColor set];
+
+    // Stroke the bottom of the infobar.
     NSRect borderRect, contentRect;
     NSDivideRect(bounds, &borderRect, &contentRect, 1, NSMinYEdge);
     NSRectFillUsingOperation(borderRect, NSCompositeSourceOver);
+
+    // Re-stroke the top because the tip will have no stroke. This will draw
+    // over the divider drawn by the bottom of the tabstrip.
+    [topPath stroke];
   }
 
   // Add an inner stroke.
+  const CGFloat kHighlightTipHeight = infobars::kTipHeight - 1;
+  NSBezierPath* highlightPath = [NSBezierPath bezierPath];
+  [highlightPath moveToPoint:NSMakePoint(NSMinX(bounds), NSMaxY(bounds) - 1)];
+  [highlightPath relativeLineToPoint:NSMakePoint(kTipXOffset + 1, 0)];
+  [highlightPath relativeLineToPoint:NSMakePoint(kHalfWidth - 1,
+                                                 kHighlightTipHeight)];
+  [highlightPath relativeLineToPoint:NSMakePoint(kHalfWidth - 1,
+                                                 -kHighlightTipHeight)];
+  [highlightPath lineToPoint:NSMakePoint(NSMaxX(bounds), NSMaxY(bounds) - 1)];
+
   [[NSColor colorWithDeviceWhite:1.0 alpha:1.0] setStroke];
-  NSAffineTransform* transform = [NSAffineTransform transform];
-  [transform translateXBy:0.0 yBy:-1.0];
-  [topPath transformUsingAffineTransform:transform];
-  [topPath stroke];
+  [highlightPath stroke];
 }
 
 - (BOOL)mouseDownCanMoveWindow {
   return NO;
 }
 
 // This view is intentionally not opaque because it overlaps with the findbar.
 
 - (BOOL)accessibilityIsIgnored {
   return NO;
 }
 
 - (id)accessibilityAttributeValue:(NSString*)attribute {
   if ([attribute isEqual:NSAccessibilityRoleAttribute])
     return NSAccessibilityGroupRole;
 
   return [super accessibilityAttributeValue:attribute];
 }
 
 @end