Revert of Make SkGraphics::Term a no-op, stop calling it.

src/core/SkPaint.cpp

Index: src/core/SkPaint.cpp
diff --git a/src/core/SkPaint.cpp b/src/core/SkPaint.cpp
index e15c1a74dbb1b954f65ea91e547a59a733c28208..c1097204c4d7ae40777793d4f51cf53321e3d807 100644
--- a/src/core/SkPaint.cpp
+++ b/src/core/SkPaint.cpp
@@ -1525,6 +1525,18 @@
     return *gMaskGamma;
 }
 
+/*static*/ void SkPaint::Term() {
+    SkAutoMutexAcquire ama(gMaskGammaCacheMutex);
+
+    SkSafeUnref(gLinearMaskGamma);
+    gLinearMaskGamma = nullptr;
+    SkSafeUnref(gMaskGamma);
+    gMaskGamma = nullptr;
+    SkDEBUGCODE(gContrast = SK_ScalarMin;)
+    SkDEBUGCODE(gPaintGamma = SK_ScalarMin;)
+    SkDEBUGCODE(gDeviceGamma = SK_ScalarMin;)
+}
+
 /**
  *  We ensure that the rec is self-consistent and efficient (where possible)
  */