Set GeometryBufferMapThreshold defaults

include/gpu/GrContextOptions.h

Index: include/gpu/GrContextOptions.h
diff --git a/include/gpu/GrContextOptions.h b/include/gpu/GrContextOptions.h
index d8d59fac3a89186a6705279f446ef5c2ca978271..8388dc5747f0dfe46e1c5b6ce31972b180fa2532 100644
--- a/include/gpu/GrContextOptions.h
+++ b/include/gpu/GrContextOptions.h
@@ -16,7 +16,7 @@ struct GrContextOptions {
         , fSuppressPrints(false)
         , fMaxTextureSizeOverride(SK_MaxS32)
         , fSuppressDualSourceBlending(false)
-        , fGeometryBufferMapThreshold(1 << 15) {}
+        , fGeometryBufferMapThreshold(-1) {}
 
     // EXPERIMENTAL
     // May be removed in the future, or may become standard depending
@@ -37,7 +37,7 @@ struct GrContextOptions {
         map a GrGeometryBuffer to update its contents. It will use map() if the
         size of the updated region is greater than the threshold. Otherwise it will
         use updateData(). */
-    size_t  fGeometryBufferMapThreshold;
+    int  fGeometryBufferMapThreshold;

[bsalomon, 2015/06/01 13:53:06]

This comment is a bit impl specific (map() and updateData() are methods on a
internal class). Maybe update the comment to say that this is the threshold
above which we will use a buffer mapping API to map vertex and index buffers to
CPU memory in order to update them. Also, should probably document that -1
indicates that the GrContext should deduce a value.

 };
 
 #endif