--- a/content/base/src/nsXMLHttpRequest.cpp
+++ b/content/base/src/nsXMLHttpRequest.cpp
@@ -1319,30 +1319,53 @@ nsXMLHttpRequest::Abort()
 
 /* string getAllResponseHeaders (); */
 NS_IMETHODIMP
 nsXMLHttpRequest::GetAllResponseHeaders(char **_retval)
 {
   NS_ENSURE_ARG_POINTER(_retval);
   *_retval = nsnull;
 
+  // If the state is UNSENT or OPENED,
+  // return the empty string and terminate these steps.
+  if (mState & (XML_HTTP_REQUEST_UNSENT |
+                XML_HTTP_REQUEST_OPENED | XML_HTTP_REQUEST_SENT)) {
+    *_retval = ToNewCString(EmptyString());
+    return NS_OK;
+  }
+
   if (mState & XML_HTTP_REQUEST_USE_XSITE_AC) {
     *_retval = ToNewCString(EmptyString());
     return NS_OK;
   }
 
   nsCOMPtr<nsIHttpChannel> httpChannel = GetCurrentHttpChannel();
 
   if (httpChannel) {
     nsRefPtr<nsHeaderVisitor> visitor = new nsHeaderVisitor();
     nsresult rv = httpChannel->VisitResponseHeaders(visitor);
     if (NS_SUCCEEDED(rv))
       *_retval = ToNewCString(visitor->Headers());
+  } else if (mChannel) {
+    // Even non-http channels supply content type.
+    nsCString value;
+    if (NS_SUCCEEDED(mChannel->GetContentType(value))) {
+      nsCString headers;
+      headers.Append("Content-Type: ");
+      headers.Append(value);
+      if (NS_SUCCEEDED(mChannel->GetContentCharset(value)) &&
+          !value.IsEmpty()) {
+        headers.Append(";charset=");
+        headers.Append(value);
+      }
+      headers.Append('\n');
+      *_retval = ToNewCString(headers);
+    }
   }
- 
+
   if (!*_retval) {
     *_retval = ToNewCString(EmptyString());
   }
 
   return NS_OK;
 }
 
 /* ACString getResponseHeader (in AUTF8String header); */
@@ -1351,16 +1374,47 @@ nsXMLHttpRequest::GetResponseHeader(cons
                                     nsACString& _retval)
 {
   nsresult rv = NS_OK;
   _retval.SetIsVoid(true);
 
   nsCOMPtr<nsIHttpChannel> httpChannel = GetCurrentHttpChannel();
 
   if (!httpChannel) {
+    // If the state is UNSENT or OPENED,
+    // return null and terminate these steps.
+    if (mState & (XML_HTTP_REQUEST_UNSENT |
+                  XML_HTTP_REQUEST_OPENED | XML_HTTP_REQUEST_SENT)) {
+      return NS_OK;
+    }
+
+    // Even non-http channels supply content type.
+    // Remember we don't leak header information from denied cross-site
+    // requests.
+    nsresult status;
+    if (!mChannel ||
+        NS_FAILED(mChannel->GetStatus(&status)) ||
+        NS_FAILED(status) ||
+        !header.LowerCaseEqualsASCII("content-type")) {
+      return NS_OK;
+    }
+
+    if (NS_FAILED(mChannel->GetContentType(_retval))) {
+      // Means no content type
+      _retval.SetIsVoid(true);
+      return NS_OK;
+    }
+
+    nsCString value;
+    if (NS_SUCCEEDED(mChannel->GetContentCharset(value)) &&
+        !value.IsEmpty()) {
+      _retval.Append(";charset=");
+      _retval.Append(value);
+    }
+
     return NS_OK;
   }
 
   // See bug #380418. Hide "Set-Cookie" headers from non-chrome scripts.
   bool chrome = false; // default to false in case IsCapabilityEnabled fails
   IsCapabilityEnabled("UniversalXPConnect", &chrome);
   if (!chrome &&
        (header.LowerCaseEqualsASCII("set-cookie") ||

--- a/content/base/test/test_XHR.html
+++ b/content/base/test/test_XHR.html
@@ -17,43 +17,52 @@ SimpleTest.waitForExplicitFinish();
 
 var gen = runTests();
 function continueTest() { gen.next(); }
 
 function runTests() {
 
 var path = "/tests/content/base/test/";
 
-var passFiles = [['file_XHR_pass1.xml', 'GET', 200],
-                 ['file_XHR_pass2.txt', 'GET', 200],
-                 ['file_XHR_pass3.txt', 'GET', 200],
-                 ['data:text/xml,%3Cres%3Ehello%3C/res%3E%0A', 'GET', 0],
-                 ['data:text/plain,hello%20pass%0A', 'GET', 0],
+var passFiles = [['file_XHR_pass1.xml', 'GET', 200, 'text/xml'],
+                 ['file_XHR_pass2.txt', 'GET', 200, 'text/plain'],
+                 ['file_XHR_pass3.txt', 'GET', 200, 'text/plain'],
+                 ['data:text/xml,%3Cres%3Ehello%3C/res%3E%0A', 'GET', 0, 'text/xml'],
+                 ['data:text/plain,hello%20pass%0A', 'GET', 0, 'text/plain'],
+                 ['data:,foo', 'GET', 0, 'text/plain;charset=US-ASCII', 'foo'],
+                 ['data:text/plain;base64,Zm9v', 'GET', 0, 'text/plain', 'foo'],
+                 ['data:text/plain,foo#bar', 'GET', 0, 'text/plain', 'foo'],
+                 ['data:text/plain,foo%23bar', 'GET', 0, 'text/plain', 'foo#bar'],
                  ];
 
 var failFiles = [['//example.com' + path + 'file_XHR_pass1.xml', 'GET'],
                  ['ftp://localhost' + path + 'file_XHR_pass1.xml', 'GET'],
                  ['file_XHR_fail1.txt', 'GET'],
                  ];
 
 for (i = 0; i < passFiles.length; ++i) {
   xhr = new XMLHttpRequest();
+  is(xhr.getResponseHeader("Content-Type"), null, "should be null");
+  is(xhr.getAllResponseHeaders(), "", "should be empty string");
   is(xhr.responseType, "", "wrong initial responseType");
   xhr.open(passFiles[i][1], passFiles[i][0], false); 
   xhr.send(null);
   is(xhr.status, passFiles[i][2], "wrong status");
+  is(xhr.getResponseHeader("Content-Type"), passFiles[i][3], "wrong content type");
+  var headers = xhr.getAllResponseHeaders();
+  ok(/(?:^|\n)Content-Type:\s*([^\n]*)\n/i.test(headers) &&
+     RegExp.$1 === passFiles[i][3], "wrong response headers");
   if (xhr.responseXML) {
     is((new XMLSerializer()).serializeToString(xhr.responseXML.documentElement),
-       "<res>hello</res>",
-       "wrong responseXML");
-    is(xhr.response, "<res>hello</res>\n", "wrong response");
+       passFiles[i][4] || "<res>hello</res>", "wrong responseXML");
+    is(xhr.response, passFiles[i][4] || "<res>hello</res>\n", "wrong response");
   }
   else {
-    is(xhr.responseText, "hello pass\n", "wrong responseText");
-    is(xhr.response, "hello pass\n", "wrong response");
+    is(xhr.responseText, passFiles[i][4] || "hello pass\n", "wrong responseText");
+    is(xhr.response, passFiles[i][4] || "hello pass\n", "wrong response");
   }
 }
 
 for (i = 0; i < failFiles.length; ++i) {
   xhr = new XMLHttpRequest();
   var didthrow = false;
   try {
     xhr.open(failFiles[i][1], failFiles[i][0], false);