Require SK_DECLARE_STATIC_LAZY_PTR is used in global scope.

Function- or method- local scope isn't threadsafe; the pointer is generally
zero-initialized on first use in function scope (i.e. lazily... we have to go
deeper), but for globals we can be pretty sure the linker will do that for us.

BUG=skia:

No public API changes.
TBR=reed@google.com

Review URL: https://codereview.chromium.org/651723003
diff --git a/src/core/SkGlyphCache.cpp b/src/core/SkGlyphCache.cpp
index ab816f9..17f4236 100755
--- a/src/core/SkGlyphCache.cpp
+++ b/src/core/SkGlyphCache.cpp
@@ -29,9 +29,10 @@
 
 }  // namespace
 
+SK_DECLARE_STATIC_LAZY_PTR(SkGlyphCache_Globals, globals, create_globals);
+
 // Returns the shared globals
 static SkGlyphCache_Globals& getSharedGlobals() {
-    SK_DECLARE_STATIC_LAZY_PTR(SkGlyphCache_Globals, globals, create_globals);
     return *globals.get();
 }