--- a/docshell/test/browser/browser.ini
+++ b/docshell/test/browser/browser.ini
@@ -25,16 +25,18 @@ support-files =
   file_bug234628-8-child.html
   file_bug234628-8.html
   file_bug234628-9-child.html
   file_bug234628-9.html
   file_bug420605.html
   file_bug503832.html
   file_bug655270.html
   file_bug670318.html
+  file_bug852909.pdf
+  file_bug852909.png
   file_bug941562-child.html
   file_bug941562.html
   print_postdata.sjs
   test-form_sjis.html
 
 [browser_bug134911.js]
 [browser_bug234628-1.js]
 [browser_bug234628-10.js]
@@ -54,13 +56,14 @@ support-files =
 [browser_bug422543.js]
 [browser_bug441169.js]
 [browser_bug503832.js]
 [browser_bug554155.js]
 [browser_bug655270.js]
 [browser_bug655273.js]
 [browser_bug670318.js]
 [browser_bug673467.js]
+[browser_bug852909.js]
 [browser_bug92473.js]
 [browser_bug941562.js]
 [browser_loadDisallowInherit.js]
 [browser_loadURI.js]
 [browser_search_notification.js]

new file mode 100644
--- /dev/null
+++ b/docshell/test/browser/browser_bug852909.js
@@ -0,0 +1,33 @@
+var rootDir = "http://mochi.test:8888/browser/docshell/test/browser/";
+
+function test() {
+  waitForExplicitFinish();
+
+  gBrowser.selectedTab = gBrowser.addTab(rootDir + "file_bug852909.png");
+  gBrowser.selectedBrowser.addEventListener("load", image, true);
+}
+
+function image(event) {
+  if (event.target != gBrowser.contentDocument) {
+    return;
+  }
+  gBrowser.selectedBrowser.removeEventListener("load", image, true);
+
+  ok(!gBrowser.docShell.mayEnableCharacterEncodingMenu, "Docshell should say the menu should be disabled for images.");
+
+  gBrowser.removeCurrentTab();
+  gBrowser.selectedTab = gBrowser.addTab(rootDir + "file_bug852909.pdf");
+  gBrowser.selectedBrowser.addEventListener("load", pdf, true);
+}
+
+function pdf(event) {
+  if (event.target != gBrowser.contentDocument) {
+    return;
+  }
+  gBrowser.selectedBrowser.removeEventListener("load", pdf, true);
+
+  ok(!gBrowser.docShell.mayEnableCharacterEncodingMenu, "Docshell should say the menu should be disabled for PDF.js.");
+
+  gBrowser.removeCurrentTab();
+  finish();
+}

new file mode 100644
index e69de29bb2d1d6434b8b29ae775ad8c2e48c5391..89066463f1013406536fec88813da93abca5483a
GIT binary patch
literal 1568
zc$~FVL2eT<6osu%z|xya?IQ8m6VHsRs*7eCT0v>rR063&XfoqWTr%U-aY*0@oQfMD
zw%mdpJFwkJGQwrSf+$k#=jZ?5fB!ps!*tNW-4Fr{11QIL;OGdTVOH`5BnG(#=;q^`
zL)6c7Hj^bdJ_fulERnP>JaF7KfL@4V0dHYwufw+h_2shG5Vx*|k6yKT6*tr-@ikw_
zrOJ&G%X@P<zT>$zYlzOP046THiHU|v<|D3Qv_&p>A+i&>hPQ#iaAdw#hmvz2l(jZF
z7qHh<J6%>|h_T!46!%(+U-G)tQ%E<Ig;qSPz&*fLfeUSa@(MVisRUOxOhan|(k38b
z8zgFwTjNGLfar#=wJp^+(>FFYtavA6r!MjQY}^89v>a=PxIh5C$||=B02+vy=E`&m
z4Q83<DbHoWZNpxR!qkT&fX=umr`j$1awgSip5+|k;K8dCp%+80`m&nK+BPoPn#2Au
zXZ=0@`SnZidGPJ*^vSayzn=Pzu%-wcZxENqE>Oxph@4+PKiM9&$Mt^}g2}&Ef{9<s
zX5=^fo=>5VwH8M{F>be8=oyFm6EWlO#>+CHgaz!t4m;1ZkacPdf&1wp32=xpA((_T
zAck-ui@%<k7ga2CW9hz|nv1Ly`Fj|3qb}>j(9lUINIFKxm612qdVYw|YPISL%dQ-|
zD^+>Ws$;GA1emvxfMEN95v3u86S&1}L)=Nd!zlAGj1vzdEb_20j(v<#59@`YkI|lo
zMHKs3<m-zb(UMR<M-mesOZ?hc;Mc*3pO^JoceTpQP$)MgBk_q_@6mZZk<bm0{ezX#
WJc-?WXG*&^nOR_9Z}0SS0Dc48o19Gm

new file mode 100644
index e69de29bb2d1d6434b8b29ae775ad8c2e48c5391..c7510d388f2a823f406bcf4403cd1ae8b5e97e7b
GIT binary patch
literal 94
zc%17D@N?(olHy`uVBq!ia0vp^0wB!61SBU+%rFB|jKx9jP7LeL$-D$|Bs^UlLp07O
pr~EkYAe4}lAaT`TRpO2;1_pb5MtQkhj&`6L22WQ%mvv4FO#qx$7OnsQ