Reduce resource limit with software compositor.

content/renderer/gpu/compositor_output_surface.cc

Index: content/renderer/gpu/compositor_output_surface.cc
diff --git a/content/renderer/gpu/compositor_output_surface.cc b/content/renderer/gpu/compositor_output_surface.cc
index 5215a90fcd32601b953b198d91146c058d2d9a0a..218b42ff0a1beb04a5810d6ada297b448af1012c 100644
--- a/content/renderer/gpu/compositor_output_surface.cc
+++ b/content/renderer/gpu/compositor_output_surface.cc
@@ -107,7 +107,7 @@ bool CompositorOutputSurface::BindToClient(
     client->SetMemoryPolicy(cc::ManagedMemoryPolicy(
         128 * 1024 * 1024,
         gpu::MemoryAllocation::CUTOFF_ALLOW_NICE_TO_HAVE,
-        cc::ManagedMemoryPolicy::kDefaultNumResourcesLimit));
+        base::SharedMemory::GetHandleLimit() / 3));
   }
 
   return true;