Emulator

As reference, the culprit commit is 1118226f270d2b44d10dd3cebd9f89fd38042680 (or the one before..?), found on GitHub commit page 68 (as of today 4th of September).

...and I've already made a forum thread on Intel's website, found at https://communities.intel.com/thread/54819 . Please feel free to submit additional info, if there's no sane way to fix this within Dolphin :)

Yep, sounds like broken buffer_storage.
Will need some real testing to figure out exactly where they are failing.

@hosode: can you post a list of supported GL extensions with that new driver, to confirm that it's really buffer storage?

If it is, @Sonicadvance1 what about DriverDetail-ing it out while debugging?

Should be fairly easy, I think they even report driver versions to us.

The release notes is found at http://downloadmirror.intel.com/24245/eng/ReleaseNotes_GFX_15_36_3907.pdf , and listed are these updates to OpenGL extensions:
Support for the following OpenGL extensions
now added:
GL_ARB_texture_view
GL_ARB_fragment_layer_viewport
GL_ARB_texture_query_levels
GL_ARB_invalidate_subdata
GL_ARB_clear_buffer_object
GL_ARB_ES3_compatibility
GL_ARB_robust_buffer_access_behavior
GL_ARB_copy_image
GL_ARB_explicit_uniform_location
GL_ARB_texture_stencil8 (OpenGL 4.4)
GL_AMD_vertex_shader_layer
GL_AMD_vertex_shader_viewport_index
GL_EXT_direct_state_access

Can you provide a list from for example http://www.realtech-vr.com/glview/download.php ? I don't trust these release notes :)

Here's some lists provided by the OpenGL extensions viewer. The latter is a .xml that is rather hard to read but more complete, the .txt includes everything from the "Report"-subpage. Turns out that OpenGL 4.3 is fully supported, but 4.4 had 2/10 result, including what else than buffer_storage (and GL_ARB_texture_stencil8). So this might have something to do with the issue.

So ARB_buffer_storage is indeed supported. Meh.

This issue is actually fixed, as PR 972 was merged yesterday.
But I still wanted to post that I reported this issue on Intel Graphics forums at https://communities.intel.com/thread/54819 , and they responded already, and the apparently have replicated the issue and are working on it.
So this might well be fixed in future updates of Intel HD drivers.

Intel contact replied this week to the thread concerning this issue at Intel graphics support forums. He said this issue has been addressed and should be fixed with next drivers (with no ETA, though). The thread is at https://communities.intel.com/thread/54819 .
I will, of course, test OGL with something from 4.0-583 to 4.0-2000, when the upcoming drivers get released.

hosode: Thanks for the update!

Intel released new drivers today, with version number 15.36.7.64.3960 a.k.a 10.18.10.3960 . I tested Dolphin version 4.0-3017 (the one before the specific workaround for Intel's drivers), and OpenGL works with the new drivers as it should! To be sure, I tested the same Dolphin version just before my update and got the black screen as I expected.
The new drivers don't support (AFAIK) Intel HD 3000/4000, but neither did the OpenGL-breaking last drivers, so no Intel users should be affected after updating their drivers, right?
I consider this fixed, and the workaround is no longer needed, especially if it affects all Intel drivers. Is it version specific, @SonicAdvance?

I've enabled buffer_storage again in PR https://github.com/dolphin-emu/dolphin/pull/1303 . I'm curious about the speedup

build is here: http://dl.dolphin-emu.org/builds/dolphin-master-4.0-3657-x64.7z

Does that mean this is fixed?

I can confirm, that On Intel HD 4600 (i5 4670S) OpenGL works flawlessly after upgrading to the latest drivers 15.36.7.64.3960 (10.18.10.3960). I tested this on those Dolhin revisions that specifically were not working with the culprit drivers that broke the buffer storage extension. I also tested the revisions that had the workaround, and then the latest revisions that have the workaround fixed. No black screens. Anyone that had the access to the broken drivers causing this issue should be able to upgrade to fixed drivers also. So yes, it's fixed.

Sorry I did not check the performance earlier as requested. I now did a quick test (with VNC connection, not really reliable) with the Dolphin version 4.0-3655 and 4.0-3657 (the first one should have the fix to bypass buffer storage with Intel, and the second one has it enabled, right?). On Super Mario Galaxy 1, I get 67-71 fps (min 62fps) on Observatory on both revisions, no noticable difference. Tested on D3D also, same fps, so no noticable difference there, either.