Remove another assertion that a reference is non-null.

This tickles a warning in Clang:
reference cannot be bound to dereferenced null pointer in well-defined
C++ code; pointer may be assumed to always convert to true
[-Wundefined-bool-conversion]

BUG=none

Review URL: https://codereview.chromium.org/1225053003
diff --git a/src/ports/SkFontHost_win.cpp b/src/ports/SkFontHost_win.cpp
index 7463dab..75e3d46 100755
--- a/src/ports/SkFontHost_win.cpp
+++ b/src/ports/SkFontHost_win.cpp
@@ -1623,7 +1623,7 @@
 }
 
 void SkScalerContext_GDI::generatePath(const SkGlyph& glyph, SkPath* path) {
-    SkASSERT(&glyph && path);
+    SkASSERT(path);
     SkASSERT(fDDC);
 
     path->reset();