[GTK] update infobars to new, harder-to-spoof versions.

This doesn't support the multiple infobar case. It does however support the following:
- There is a drop shadow over the render view content, over the toolbar area, and an arrow to the location icon.
- animations while enabling/disabling the bookmark bar, on normal page or NTP
- different infobar colors
- switching between tabs with or without infobars
- animated appearance/disappearance (animation is alpha-fade)

Popup windows don't appear to support infobars (at least I can't get an infobar to open in a popup window), but this new code doesn't cause crashes there either.

BUG=48996
TEST=manual (see above)

Review URL: http://codereview.chromium.org/3621010

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@62001 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 23 insertions, 0 deletions

diff --git a/chrome/browser/gtk/gtk_util.cc b/chrome/browser/gtk/gtk_util.cc
index 2ada5d7..f3d1f88 100644
--- a/chrome/browser/gtk/gtk_util.cc
+++ b/chrome/browser/gtk/gtk_util.cc
@@ -4,6 +4,7 @@
 
 #include "chrome/browser/gtk/gtk_util.h"
 
+#include <cairo/cairo.h>
 #include <gtk/gtk.h>
 #include <gdk/gdkx.h>
 
@@ -1106,4 +1107,26 @@ void InitLabelSizeRequestAndEllipsizeMode(GtkWidget* label) {
   gtk_label_set_ellipsize(GTK_LABEL(label), PANGO_ELLIPSIZE_END);
 }
 
+void DrawTopDropShadowForRenderView(cairo_t* cr, const gfx::Point& origin,
+    const gfx::Rect& paint_rect) {
+  const int kShadowHeight = 6;
+  gfx::Rect shadow_rect(paint_rect.x(), origin.y(),
+                        paint_rect.width(), kShadowHeight);
+
+  // Avoid this extra work if we can.
+  if (!shadow_rect.Intersects(paint_rect))
+    return;
+
+  cairo_pattern_t* shadow =
+      cairo_pattern_create_linear(0.0, shadow_rect.y(),
+                                  0.0, shadow_rect.bottom());
+  cairo_pattern_add_color_stop_rgba(shadow, 0, 0, 0, 0, 0.6);
+  cairo_pattern_add_color_stop_rgba(shadow, 1, 0, 0, 0, 0.1);
+  cairo_rectangle(cr, shadow_rect.x(), shadow_rect.y(),
+                  shadow_rect.width(), shadow_rect.height());
+  cairo_set_source(cr, shadow);
+  cairo_fill(cr);
+  cairo_pattern_destroy(shadow);
+}
+
 }  // namespace gtk_util