Fully qualify usage of ArraySizeHelper to prevent conflict.

mojo redefines ArraySizeHelper in the mojo namespace. When arraysize is used
in the mojo namespace, with both version in scope, the compiler, on android, is complaining that the reference is
not unique. To prevent this, qualify the usage of ArraySizeHelper in
base/macros.h

Review URL: https://codereview.chromium.org/804023002

Cr-Commit-Position: refs/heads/master@{#315290}

base/macros.h

@@ -63,7 +63,7 @@ template <typename T, size_t N>
 char (&ArraySizeHelper(const T (&array)[N]))[N];
 #endif
 
-#define arraysize(array) (sizeof(ArraySizeHelper(array)))
+#define arraysize(array) (sizeof(::ArraySizeHelper(array)))
 
 
 // Use implicit_cast as a safe version of static_cast or const_cast

chrome/installer/mini_installer/decompress.h

@@ -8,7 +8,7 @@
 // arraysize borrowed from basictypes.h
 template <typename T, size_t N>
 char (&ArraySizeHelper(T (&array)[N]))[N];
-#define arraysize(array) (sizeof(ArraySizeHelper(array)))
+#define arraysize(array) (sizeof(::ArraySizeHelper(array)))
 
 namespace mini_installer {