Revert "Apply disable_discard_framebuffer workaround to Adreno 5xx."

This reverts commit 010e9500.

I set this workaround flag based on misreading a crash report, and
there's actually no evidence that Adreno 5xx has any bugs with
framebuffer discarding.

BUG=612474
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_optional_gpu_tests_rel;master.tryserver.chromium.mac:mac_optional_gpu_tests_rel;master.tryserver.chromium.win:win_optional_gpu_tests_rel

Review-Url: https://codereview.chromium.org/2177393003
Cr-Commit-Position: refs/heads/master@{#407677}

gpu/config/gpu_driver_bug_list_json.cc

@@ -19,7 +19,7 @@ const char kGpuDriverBugListJson[] = LONG_STRING_CONST(
 {
   "name": "gpu driver bug list",
   // Please update the version number whenever you change this file.
-  "version": "8.79",
+  "version": "8.80",
   "entries": [
     {
       "id": 1,
@@ -1755,18 +1755,6 @@ LONG_STRING_CONST(
         "unpack_overlapping_rows_separately_unpack_buffer"
       ]
     },
-    {
-      "id": 166,
-      "cr_bugs": [612474],
-      "description": "Crash reports for glDiscardFramebuffer on Adreno 530",
-      "gl_renderer": "Adreno \\(TM\\) 5.*",
-      "os": {
-        "type": "android"
-      },
-      "features": [
-        "disable_discard_framebuffer"
-      ]
-    },
     {
       "id": 167,
       "cr_bugs": [610516],