Added GYP defines to dump linux symbols for gpu perf bots and trybots.

scripts/slave/recipe_modules/gpu/api.py

Index: scripts/slave/recipe_modules/gpu/api.py
diff --git a/scripts/slave/recipe_modules/gpu/api.py b/scripts/slave/recipe_modules/gpu/api.py
index a621a9d180f0be50a08e80f0e8bff26745bc3c01..8d6d3dc4f7df211ce86b5dd05fbe2995dd593b75 100644
--- a/scripts/slave/recipe_modules/gpu/api.py
+++ b/scripts/slave/recipe_modules/gpu/api.py
@@ -64,6 +64,10 @@ class GpuApi(recipe_api.RecipeApi):
     self.m.chromium.c.gyp_env.GYP_DEFINES.pop('use_ash', None)
     self.m.chromium.c.gyp_env.GYP_DEFINES.pop('use_aura', None)
 
+    # To print out callstacks on linux bots, we must output symbols as well.
+    if self.m.platform.is_linux:
+      self.m.chromium.c.gyp_env.GYP_DEFINES['linux_dump_symbols'] = 1
+
     # Enable archiving the GPU tests' isolates in chrome_tests.gypi.
     # The non-GPU trybots build the "all" target, and these tests
     # shouldn't be built or run on those bots.