Generate path names on the client side

Pre-allocates a range of path names and manages allocations within
that range on the client side. This allows us to generate new path
objects in a feed-forward manner that doesn't require round trips to
the GL server.

BUG=skia:
R=bsalomon@google.com, markkilgard@gmail.com

Author: cdalton@nvidia.com

Review URL: https://codereview.chromium.org/304403003
diff --git a/gyp/tests.gypi b/gyp/tests.gypi
index 7a32da2..6af8e91 100644
--- a/gyp/tests.gypi
+++ b/gyp/tests.gypi
@@ -119,6 +119,7 @@
     '../tests/MessageBusTest.cpp',
     '../tests/MetaDataTest.cpp',
     '../tests/MipMapTest.cpp',
+    '../tests/NameAllocatorTest.cpp',
     '../tests/ObjectPoolTest.cpp',
     '../tests/OSPathTest.cpp',
     '../tests/OnceTest.cpp',