Omit multipicturedraw tests for Valgrind_PreAbandonGpuContext bot.

Bug: skia:6575
Change-Id: Ie937962e6a4f2dd989efca8ad94d35ad058bc87c
No-Try: true
Reviewed-on: https://skia-review.googlesource.com/20226
Reviewed-by: Robert Phillips <robertphillips@google.com>
Commit-Queue: Ben Wagner <benjaminwagner@google.com>

infra/bots/recipes/test.expected/Test-Ubuntu-GCC-ShuttleA-GPU-GTX550Ti-x86_64-Release-Valgrind_PreAbandonGpuContext.json

@@ -494,6 +494,7 @@
       ".SRW",
       "--match",
       "~Threaded",
+      "~multipicturedraw_",
       "--verbose",
       "--preAbandonGpuContext"
     ],

infra/bots/recipes/test.py

@@ -389,6 +389,10 @@ def dm_flags(bot):
   if 'Valgrind' in bot: # skia:3021
     match.append('~Threaded')
 
+  if 'Valgrind' in bot and 'PreAbandonGpuContext' in bot:
+    # skia:6575
+    match.append('~multipicturedraw_')
+
   if 'CommandBuffer' in bot:
     # https://crbug.com/697030
     match.append('~HalfFloatAlphaTextureTest')