diff -r 000000000000 -r 6474c204b198 docshell/test/browser/browser_bug92473.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/docshell/test/browser/browser_bug92473.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,55 @@
+/* The test text as octets for reference
+ * %83%86%83%6a%83%52%81%5b%83%68%82%cd%81%41%82%b7%82%d7%82%c4%82%cc%95%b6%8e%9a%82%c9%8c%c5%97%4c%82%cc%94%d4%8d%86%82%f0%95%74%97%5e%82%b5%82%dc%82%b7
+ */
+
+/* The test text decoded correctly as Shift_JIS */
+const rightText="\u30E6\u30CB\u30B3\u30FC\u30C9\u306F\u3001\u3059\u3079\u3066\u306E\u6587\u5B57\u306B\u56FA\u6709\u306E\u756A\u53F7\u3092\u4ED8\u4E0E\u3057\u307E\u3059";
+
+/* The test text decoded incorrectly as Windows-1251. This is the "right" wrong
+   text; anything else is unexpected. */
+const wrongText="\u0453\u2020\u0453\u006A\u0453\u0052\u0403\u005B\u0453\u0068\u201A\u041D\u0403\u0041\u201A\u00B7\u201A\u0427\u201A\u0414\u201A\u041C\u2022\u00B6\u040B\u0459\u201A\u0419\u040A\u0415\u2014\u004C\u201A\u041C\u201D\u0424\u040C\u2020\u201A\u0440\u2022\u0074\u2014\u005E\u201A\u00B5\u201A\u042C\u201A\u00B7";
+
+function testContent(text) {
+  is(gBrowser.contentDocument.getElementById("testpar").innerHTML, text,
+     "<p> contains expected text");
+  is(gBrowser.contentDocument.getElementById("testtextarea").innerHTML, text,
+     "<textarea> contains expected text");
+  is(gBrowser.contentDocument.getElementById("testinput").value, text,
+     "<input> contains expected text");
+}
+
+function afterOpen() {
+  gBrowser.selectedBrowser.removeEventListener("load", afterOpen, true);
+  gBrowser.selectedBrowser.addEventListener("load", afterChangeCharset, true);
+
+  /* Test that the content on load is the expected wrong decoding */
+  testContent(wrongText);
+
+  /* Force the page encoding to Shift_JIS */
+  BrowserSetForcedCharacterSet("Shift_JIS");
+}
+  
+function afterChangeCharset() {
+  gBrowser.selectedBrowser.removeEventListener("load", afterChangeCharset, true);
+
+  /* test that the content is decoded correctly */
+  testContent(rightText);
+  gBrowser.removeCurrentTab();
+  finish();
+}
+
+function test() {
+  waitForExplicitFinish();
+
+  // Get the local directory. This needs to be a file: URI because chrome: URIs
+  // are always UTF-8 (bug 617339) and we are testing decoding from other
+  // charsets.
+  var jar = getJar(getRootDirectory(gTestPath));
+  var dir = jar ?
+              extractJarToTmp(jar) :
+              getChromeDir(getResolvedURI(gTestPath));
+  var rootDir = Services.io.newFileURI(dir).spec;
+
+  gBrowser.selectedTab = gBrowser.addTab(rootDir + "test-form_sjis.html");
+  gBrowser.selectedBrowser.addEventListener("load", afterOpen, true);
+}