919362 - "this.docShell is null" when opening lots of windows with XUL cache disabled

Status: NEW

(Firefox :: General, defect)

Description

[Jesse Ruderman]

Attachment: testcase (requires prefs; opens many windows)

With these prefs:
  user_pref("nglayout.debug.disable_xul_cache", true);
  user_pref("dom.disable_open_during_load", false);
  user_pref("dom.min_background_timeout_value", 4);

The testcase frequently hits:

[Exception... "'[JavaScript Error: "this.docShell is null" {file: "chrome://global/content/bindings/browser.xml" line: 345}]' when calling method: [nsIObserver::observe]"  nsresult: "0x80570021 (NS_ERROR_XPC_JAVASCRIPT_ERROR_WITH_DETAILS)"  location: "JS frame :: chrome://global/content/bindings/browser.xml :: get_contentWindow :: line 345"  data: yes]

Sometimes the "location:" part is different:

location: "JS frame :: chrome://browser/content/browser.js :: <TOP_LEVEL> :: line 12968"

or

location: "native frame :: <unknown filename> :: <TOP_LEVEL> :: line 0"

Comment 1

[Jesse Ruderman]

browser.xml line 345 is the contentWindow getter:

      <property name="contentWindow"
                readonly="true"
                onget="return this._contentWindow || (this._contentWindow = this.docShell.QueryInterface(Components.interfaces.nsIInterfaceRequestor).getInterface(Components.interfaces.nsIDOMWindow));"/>