AAPT: Continuation of public/private attribute fix

XML files like layouts are now scanned and checked
for v21 attributes. If those kinds of attributes
are found, then we remove them in the original
version and synthesize a new xml file under the
v21 configuration.

Bug:17520380
Change-Id: Icf984cb96134180a2e35349c1dbf2cef9a8f0bda
diff --git a/tools/aapt/AaptAssets.h b/tools/aapt/AaptAssets.h
index 3fc9f81..d809c5b 100644
--- a/tools/aapt/AaptAssets.h
+++ b/tools/aapt/AaptAssets.h
@@ -104,6 +104,9 @@
 struct AaptGroupEntry
 {
 public:
+    AaptGroupEntry() {}
+    AaptGroupEntry(const ConfigDescription& config) : mParams(config) {}
+
     bool initFromDirName(const char* dir, String8* resType);
 
     inline const ConfigDescription& toParams() const { return mParams; }