Enhanced Protected Mode support

src/plugin/AdblockPlus.rgs

 HKCR
 {
         AdblockPlus.AdblockPlus.1 = s 'AdblockPlus Class'

[Wladimir Palant, 2013/09/17 07:53:48]

Mind converting the tabs to spaces in this file? Currently the indentation looks
off.

         {
                 CLSID = s '{FFCB3198-32F3-4E8B-9539-4324694ED664}'
         }
         AdblockPlus.AdblockPlus = s 'AdblockPlus Class'
         {
                 CLSID = s '{FFCB3198-32F3-4E8B-9539-4324694ED664}'
                 CurVer = s 'AdblockPlus.AdblockPlus.1'
         }
         NoRemove CLSID
         {
@@ skipping 32 matching lines @@
                                                 'Browser Helper Objects'
                                                 {
                                                         {FFCB3198-32F3-4E8B-9539-4324694ED664}
                                                         {
                                                                 val 'NoExplorer' = d '1'
                                                         }
                                                 }
                                         }
                                 }
                         }
+      'Internet Explorer'
+      {
+        'Low Rights'
+        {
+          ElevationPolicy
+          {
+            {FFCB3198-32F3-4E8B-9539-4324694ED664} = s 'ABP'
+            {
+              val 'Policy' = d '3'
+              val 'AppName' = s 'AdblockPlusEngine.exe'
+              val 'AppPath' = s 'C:\Program Files\Adblock Plus for IE'

[Wladimir Palant, 2013/09/17 07:53:48]

I would prefer having the DLL pass in a custom parameter deduced from its own
path. Not necessary for this release (custom install script parameters seem
non-trivial) but should be addressed later.

[Oleksandr, 2013/09/17 08:27:19]

I agree with that. However, FYI, I don't think I've mentioned before that in
order for IE in EPM to load our plugin at all - it has to be in Program Files
folder. So some custom dev builds might fail here.

[Felix Dahlke, 2013/09/17 09:13:51]

That's not great, will complicate development a bit, eh? 

More on topic: I don't think we can hard code this in the long term. Even if
we're 100% sure it'll be in Program Files, it's not necessarily on the C drive.
It's quite possible to use a different drive letter for the Windows partition.

[Wladimir Palant, 2013/09/17 10:12:39]

Well, setting up the development environment should require elevation anyway -
meaning that we can create a junction point under Program Files pointing to the
build dir and register the DLL under that path.
Of course not, the Program Files directory can be anywhere. The hardcoded path
here is only acceptable right now because it isn't used for anything but testing
(the installer doesn't use the auto-registration).

+            }
+          }
+        }
+      }
                 }
         }
 }