Introduce anydpi density resource qualifier

This is meant to be used with scaleable vector
drawables, and are chosen as the best match unless
there is a configuration that matches the density
requested exactly.

Bug:17007265
Change-Id: Ic3288d0236fe0bff20bb1599aba2582c25b0db32
diff --git a/libs/androidfw/tests/TestHelpers.h b/libs/androidfw/tests/TestHelpers.h
index 75a233a..fe2e5ce 100644
--- a/libs/androidfw/tests/TestHelpers.h
+++ b/libs/androidfw/tests/TestHelpers.h
@@ -3,6 +3,7 @@
 
 #include <ostream>
 
+#include <androidfw/ResourceTypes.h>
 #include <utils/String8.h>
 #include <utils/String16.h>
 
@@ -14,4 +15,16 @@
     return out << android::String8(str).string();
 }
 
+namespace android {
+
+static inline bool operator==(const android::ResTable_config& a, const android::ResTable_config& b) {
+    return memcmp(&a, &b, sizeof(a)) == 0;
+}
+
+static inline ::std::ostream& operator<<(::std::ostream& out, const android::ResTable_config& c) {
+    return out << c.toString().string();
+}
+
+} // namespace android
+
 #endif // __TEST_HELPERS_H