pdf.js/extensions/chrome/manifest.json

{
  "manifest_version": 2,
  "name": "PDF Viewer",
  "version": "PDFJSSCRIPT_VERSION",
  "description": "Uses HTML5 to display PDF files directly in Chrome.",
  "icons": {
    "128": "icon128.png",
    "48": "icon48.png",
    "16": "icon16.png"
  },
  "permissions": [
    "webRequest", "webRequestBlocking",
    "<all_urls>",
    "tabs"
  ],
  "content_scripts": [{
      "matches": [
          "*://*/*.pdf*",
          "*://*/*.PDF*"
       ],
       "css": ["hide-xhtml-error.css"]
  }],
  "background": {
    "page": "pdfHandler.html"
  },
  "web_accessible_resources": [
    "patch-worker.js",
    "content/*"
  ]
}