[Extensions] Don't allow content scripts on the New Tab Page

chrome/test/data/extensions/api_test/content_scripts/ntp/manifest.json

Index: chrome/test/data/extensions/api_test/content_scripts/ntp/manifest.json
diff --git a/chrome/test/data/extensions/api_test/content_scripts/ntp/manifest.json b/chrome/test/data/extensions/api_test/content_scripts/ntp/manifest.json
new file mode 100644
index 0000000000000000000000000000000000000000..ae167737f3620b72c0d768d458ba9e9e0b495a5e
--- /dev/null
+++ b/chrome/test/data/extensions/api_test/content_scripts/ntp/manifest.json
@@ -0,0 +1,13 @@
+{
+  "name": "New Tab Page Injector",
+  "version": "0.1",
+  "manifest_version": 2,
+  "description": "Injects in the NTP",
+  "content_scripts": [{
+    "matches": ["*://*/*"],
+    "js": ["script.js"],
+    "run_at": "document_start"

[karandeepb, 2017/07/18 21:06:25]

For my own knowledge, why didn't document_start/window.didInject work? 

[Devlin, 2017/07/18 21:12:49]

window.didInject didn't work because the content script (or script added by
tabs.executeScript) executes in an isolated world, so the variables aren't
exposed to the main world - which is where content::ExecuteScriptAndExtract* are
executed.  As a workaround, we can modify the DOM, so that the changes are
visible to the main world script context, even though they were performed in an
isolated world.  So that leads us to using document.title instead of
window.didInject.  From there, document_start is just too early in the rendering
process for document.title to be assigned, so we need to wait 'til at least
document_end.

[karandeepb, 2017/07/18 21:27:18]

Makes sense! Thanks.

+  }],
+  "background": {"scripts": ["background.js"]},
+  "permissions": ["tabs", "*://*/*"]
+}