Revert of Consolidate GPU buffer implementations

src/gpu/gl/GrGLCaps.cpp

Index: src/gpu/gl/GrGLCaps.cpp
diff --git a/src/gpu/gl/GrGLCaps.cpp b/src/gpu/gl/GrGLCaps.cpp
index 51974d4c02a2b0133976aea1ce88ee91f31cc37e..50a74febe7a6d48dd6bd3494cda51aaa0a46e9ae 100644
--- a/src/gpu/gl/GrGLCaps.cpp
+++ b/src/gpu/gl/GrGLCaps.cpp
@@ -400,14 +400,14 @@
 
     // On many GPUs, map memory is very expensive, so we effectively disable it here by setting the
     // threshold to the maximum unless the client gives us a hint that map memory is cheap.
-    if (fBufferMapThreshold < 0) {
+    if (fGeometryBufferMapThreshold < 0) {
         // We think mapping on Chromium will be cheaper once we know ahead of time how much space
         // we will use for all GrBatchs. Right now we might wind up mapping a large buffer and using
         // a small subset.
 #if 0
-        fBufferMapThreshold = kChromium_GrGLDriver == ctxInfo.driver() ? 0 : SK_MaxS32;
+        fGeometryBufferMapThreshold = kChromium_GrGLDriver == ctxInfo.driver() ? 0 : SK_MaxS32;
 #else
-        fBufferMapThreshold = SK_MaxS32;
+        fGeometryBufferMapThreshold = SK_MaxS32;
 #endif
     }