Add a PDF component extension

chrome/browser/browser_resources.grd

Index: chrome/browser/browser_resources.grd
diff --git a/chrome/browser/browser_resources.grd b/chrome/browser/browser_resources.grd
index 070bf5ad6662686f60ab17dd21eec394c546823c..77270eb880d6b505955e5c90125bce17ac3307f7 100644
--- a/chrome/browser/browser_resources.grd
+++ b/chrome/browser/browser_resources.grd
@@ -256,6 +256,7 @@
       <if expr="pp_ifdef('enable_settings_app')">
         <include name="IDR_SETTINGS_APP_MANIFEST" file="resources\settings_app\manifest.json" type="BINDATA" />
       </if>
+      <include name="IDR_PDF_MANIFEST" file="resources\pdf\manifest.json" type="BINDATA" />

[tapted, 2013/12/02 04:17:19]

nit: I think this file is vaguely sorted in <structures> and <includes>. Maybe
put around line 198.

Also, do these need to be guarded with `pp_ifdef('_google_chrome')` so it
doesn't show up in Chromium builds?

[raymes, 2013/12/04 04:54:49]

Done.
As discussed I think it's ok to include this in Chromium builds. It won't
actually get added as an extension unless the PDF plugin is present.

       <if expr="pp_ifdef('enable_google_now')">
         <include name="IDR_GOOGLE_NOW_MANIFEST" file="resources\google_now\manifest.json" type="BINDATA" />
       </if>