Added a CanHandleContentType to identify if a given instantiated docShell can handle the requested document type.

git-svn-id: svn://10.0.0.236/trunk@51841 18797224-902f-48f8-a5cc-f745e15eee43

mozilla/docshell/base/nsDocShellBase.cpp

@@ -158,6 +158,17 @@ NS_IMETHODIMP nsDocShellBase::SetParent(nsIDocShell* parent)
    return NS_ERROR_FAILURE;
 }
 
+NS_IMETHODIMP nsDocShellBase::CanHandleContentType(const PRUnichar* contentType, 
+   PRBool* canHandle)
+{
+   NS_ENSURE_ARG_POINTER(canHandle);
+   
+   NS_WARN_IF_FALSE(PR_FALSE, "Subclasses should override this method!!!!");
+
+   *canHandle = PR_FALSE;
+   return NS_OK;
+}
+
 NS_IMETHODIMP nsDocShellBase::GetPrefs(nsIPref** prefs)
 {
    NS_ENSURE_ARG_POINTER(prefs);

mozilla/docshell/base/nsIDocShell.idl

@@ -93,6 +93,11 @@ interface nsIDocShell : nsISupports
 	*/
 	attribute nsIDocShell parent;
 
+	/*
+	Returns true if the given docshell can handle the requested content type.
+	*/
+	boolean canHandleContentType(in wstring contentType);
+
 	/*
 	Prefs to use for the DocShell.
 	*/

mozilla/docshell/html/nsHTMLDocShell.cpp

@@ -21,6 +21,7 @@
  */
 
 #include "nsHTMLDocShell.h"
+#include "nsString.h"
 
 //*****************************************************************************
 //***    nsHTMLDocShell: Object Management
@@ -61,6 +62,20 @@ NS_IMPL_ISUPPORTS7(nsHTMLDocShell, nsIDocShell, nsIHTMLDocShell,
 // nsHTMLDocShell::nsIDocShell Overrides
 //*****************************************************************************   
 
+NS_IMETHODIMP nsHTMLDocShell::CanHandleContentType(const PRUnichar* contentType, 
+   PRBool* canHandle)
+{
+   NS_ENSURE_ARG_POINTER(canHandle);
+
+   nsAutoString aType(contentType);
+                                         
+   if(aType.EqualsIgnoreCase("text/html"))
+      *canHandle = PR_TRUE;
+   else   
+      *canHandle = PR_FALSE;
+   return NS_OK;
+}
+
 //*****************************************************************************
 // nsHTMLDocShell::nsIHTMLDocShell
 //*****************************************************************************   

mozilla/docshell/html/nsHTMLDocShell.h

@@ -31,6 +31,9 @@ class nsHTMLDocShell : public nsDocShellBase, public nsIHTMLDocShell
 public:
    NS_DECL_ISUPPORTS
 
+   NS_IMETHOD CanHandleContentType(const PRUnichar* contentType, PRBool* canHandle);
+
+
    NS_DECL_NSIHTMLDOCSHELL
 
    static NS_METHOD Create(nsISupports* aOuter, const nsIID& aIID, void** ppv);