Speed up GrResourceCache add and lookup by using TDynamicHash

Speed up GrResourceCache add and lookup by using TDynamicHash

Speed up GrResourceCache add and lookup by using TDynamicHash instead
of GrTHashTable. GrTHashTable spends most of its time memmoving the
array elements while sorting after an add. Lookup is not particularly
fast either.

R=mtklein@google.com, bsalomon@google.com, reed@google.com

Author: kkinnunen@nvidia.com

Review URL: https://codereview.chromium.org/91453002

git-svn-id: http://skia.googlecode.com/svn/trunk@13122 2bbb7eff-a529-9590-31e7-b0007b416f81