[M43] use floor for mip-level choice

src/core/SkMipMap.cpp

Index: src/core/SkMipMap.cpp
diff --git a/src/core/SkMipMap.cpp b/src/core/SkMipMap.cpp
index 1b410856e4ed07d7a134897f4bb43fdae6327d52..4a548b8562c2b8ed0f87939466306939d30e6129 100644
--- a/src/core/SkMipMap.cpp
+++ b/src/core/SkMipMap.cpp
@@ -334,8 +334,9 @@ bool SkMipMap::extractLevel(SkScalar scale, Level* levelPtr) const {
         return false;
     }
     SkASSERT(L >= 0);
-    int level = SkScalarRoundToInt(L);
-//    SkDebugf("mipmap scale=%g L=%g level=%d\n", scale, L, level);
+//    int rndLevel = SkScalarRoundToInt(L);
+    int level = SkScalarFloorToInt(L);
+//    SkDebugf("mipmap scale=%g L=%g level=%d rndLevel=%d\n", scale, L, level, rndLevel);
 
     SkASSERT(level >= 0);
     if (level <= 0) {