Change explanation string for the Subresource Filter prompt.

chrome/browser/ui/cocoa/content_settings/content_setting_bubble_cocoa.mm

Index: chrome/browser/ui/cocoa/content_settings/content_setting_bubble_cocoa.mm
diff --git a/chrome/browser/ui/cocoa/content_settings/content_setting_bubble_cocoa.mm b/chrome/browser/ui/cocoa/content_settings/content_setting_bubble_cocoa.mm
index e0e09f2c99a5d4b49476dfc412164237bc71e119..1d3b604386144b674d6173dc957af28d1ca08e25 100644
--- a/chrome/browser/ui/cocoa/content_settings/content_setting_bubble_cocoa.mm
+++ b/chrome/browser/ui/cocoa/content_settings/content_setting_bubble_cocoa.mm
@@ -212,6 +212,7 @@ class ContentSettingBubbleWebContentsObserverBridge
                        referenceFrame:(NSRect)referenceFrame;
 - (void)initializeBlockedPluginsList;
 - (void)initializeTitle;
+- (void)initializeMessage;
 - (void)initializeRadioGroup;
 - (void)initializeItemList;
 - (void)initializeGeoLists;
@@ -329,6 +330,24 @@ const ContentTypeToNibPath kNibPaths[] = {
   [titleLabel_ setFrame:titleFrame];
 }
 
+- (void)initializeMessage {
+  if (!messageLabel_)
+    return;
+
+  NSString* label = base::SysUTF16ToNSString(
+      contentSettingBubbleModel_->bubble_content().message);
+  [messageLabel_ setStringValue:label];
+
+  CGFloat deltaY = [GTMUILocalizerAndLayoutTweaker
+      sizeToFitFixedWidthTextField:messageLabel_];
+  NSRect windowFrame = [[self window] frame];
+  windowFrame.size.height += deltaY;
+  [[self window] setFrame:windowFrame display:NO];
+  NSRect messageFrame = [messageLabel_ frame];
+  messageFrame.origin.y -= deltaY;
+  [messageLabel_ setFrame:messageFrame];
+}
+
 - (void)initializeRadioGroup {
   // NOTE! Tags in the xib files must match the order of the radio buttons
   // passed in the radio_group and be 1-based, not 0-based.
@@ -769,6 +788,7 @@ const ContentTypeToNibPath kNibPaths[] = {
   [self initManageDoneButtons];
 
   [self initializeTitle];
+  [self initializeMessage];
 
   // Note that the per-content-type methods and |initializeRadioGroup| below
   // must be kept in the correct order, as they make interdependent adjustments