Fix the misalignment on CrOS of the tab background images

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

Index: chrome/browser/ui/cocoa/tabs/tab_view.mm
diff --git a/chrome/browser/ui/cocoa/tabs/tab_view.mm b/chrome/browser/ui/cocoa/tabs/tab_view.mm
index e4271e259f3474d02f46c9478764ecfd08b7377b..d4abeb38ea361716baef34b35c4056ac74c05756 100644
--- a/chrome/browser/ui/cocoa/tabs/tab_view.mm
+++ b/chrome/browser/ui/cocoa/tabs/tab_view.mm
@@ -302,6 +302,12 @@ const CGFloat kRapidCloseDist = 2.5;
 
 // Draws the active tab background.
 - (void)drawFillForActiveTab:(NSRect)dirtyRect {
+  gfx::ScopedNSGraphicsContextSaveGState scopedGState;
+  NSGraphicsContext* context = [NSGraphicsContext currentContext];
+  NSPoint position = [[self window]
+      themeImagePositionForAlignment:THEME_IMAGE_ALIGN_WITH_TAB_STRIP];
+  [context cr_setPatternPhase:position forView:self];
+
   NSColor* backgroundImageColor = [self backgroundColorForSelected:YES];
   [backgroundImageColor set];
 
@@ -323,9 +329,6 @@ const CGFloat kRapidCloseDist = 2.5;
 
   ThemeService* themeProvider =
       static_cast<ThemeService*>([[self window] themeProvider]);
-  NSPoint position = [[self window]
-      themeImagePositionForAlignment: THEME_IMAGE_ALIGN_WITH_TAB_STRIP];
-  [context cr_setPatternPhase:position forView:self];
 
   CGImageRef mask([self tabClippingMask]);
   CGRect maskBounds = CGRectMake(0, 0, maskCacheWidth_, kMaskHeight);
@@ -342,7 +345,10 @@ const CGFloat kRapidCloseDist = 2.5;
   if (dirtyRect.origin.y < 1)
     dirtyRect.origin.y = 2 * [self cr_lineWidth];
 
-  // Draw the tab background.
+  // Draw the tinted frame image.
+  NSPoint position = [[self window]
+      themeImagePositionForAlignment:THEME_IMAGE_ALIGN_WITH_FRAME];
+  [context cr_setPatternPhase:position forView:self];
   NSColor* backgroundImageColor = [self backgroundColorForSelected:NO];
   [backgroundImageColor set];
 
@@ -354,6 +360,22 @@ const CGFloat kRapidCloseDist = 2.5;
   else
     NSRectFillUsingOperation(dirtyRect, NSCompositeSourceOver);
 
+  // If the theme is not the default theme, it may provide a custom overlay
+  // image. The overlay image is aligned with the top of the tab.
+  NSColor* overlayImageColor = nil;
+  if (themeProvider &&
+      themeProvider->HasCustomImage(IDR_THEME_TAB_BACKGROUND_OVERLAY)) {
+    overlayImageColor = themeProvider->GetNSImageColorNamed(
+        IDR_THEME_TAB_BACKGROUND_OVERLAY);
+  }
+  if (overlayImageColor) {
+    position = [[self window]
+        themeImagePositionForAlignment:THEME_IMAGE_ALIGN_WITH_TAB_STRIP];
+    [context cr_setPatternPhase:position forView:self];
+    [overlayImageColor set];
+    NSRectFillUsingOperation(dirtyRect, NSCompositeSourceOver);
+  }
+
   // Draw the glow for hover and the overlay for alerts.
   CGFloat hoverAlpha = [self hoverAlpha];
   CGFloat alertAlpha = [self alertAlpha];
@@ -374,7 +396,7 @@ const CGFloat kRapidCloseDist = 2.5;
     // theme machinery will make one if given a frame image. See
     // BrowserThemePack::GenerateTabBackgroundImages for details.
     BOOL hasCustomTheme = themeProvider &&
-        (themeProvider->HasCustomImage(IDR_THEME_TAB_BACKGROUND) ||
+        (themeProvider->HasCustomImage(IDR_THEME_TAB_BACKGROUND_OVERLAY) ||
          themeProvider->HasCustomImage(IDR_THEME_FRAME));
     // Draw a mouse hover gradient for the default themes.
     if (hoverAlpha > 0) {