Move an #include out of a namespace.

This is required to build Chromium's ui_base target with -fmodules, but it
seems like a good change regardless.  Including a header in a namespace is
weird.

BUG=chromium:543704

Review URL: https://codereview.chromium.org/1398843007
diff --git a/src/pdf/SkDeflate.cpp b/src/pdf/SkDeflate.cpp
index c52a460..0a5b6f9 100644
--- a/src/pdf/SkDeflate.cpp
+++ b/src/pdf/SkDeflate.cpp
@@ -11,14 +11,14 @@
 #include "SkDeflate.h"
 #include "SkStream.h"
 
-namespace {
-
 #ifdef ZLIB_INCLUDE
     #include ZLIB_INCLUDE
 #else
     #include "zlib.h"
 #endif
 
+namespace {
+
 // Different zlib implementations use different T.
 // We've seen size_t and unsigned.
 template <typename T> void* skia_alloc_func(void*, T items, T size) {