Implement compatibility support for WRITE_SDCARD permission.

Now old applications will automatically be granted it.  Also renamed it from
SDCARD_WRITE to WRITE_SDCARD to be consistent with our other permissions,
and re-arranged how we do targetSdkVersion to actually be usuable for this
kind of stuff.

Note that right now this results in basically all apps being given the
WRITE_SDCARD permission, because their targetSdkVersion is not set.  I will
be dealing with that in a future change.
diff --git a/tools/aapt/ResourceTable.h b/tools/aapt/ResourceTable.h
index 74ba326..665232b 100644
--- a/tools/aapt/ResourceTable.h
+++ b/tools/aapt/ResourceTable.h
@@ -15,6 +15,7 @@
 
 using namespace std;
 
+class XMLNode;
 class ResourceTable;
 
 enum {
@@ -34,6 +35,12 @@
                         ResourceTable* table,
                         int options = XML_COMPILE_STANDARD_RESOURCE);
 
+status_t compileXmlFile(const sp<AaptAssets>& assets,
+                        const sp<XMLNode>& xmlTree,
+                        const sp<AaptFile>& target,
+                        ResourceTable* table,
+                        int options = XML_COMPILE_STANDARD_RESOURCE);
+
 status_t compileResourceFile(Bundle* bundle,
                              const sp<AaptAssets>& assets,
                              const sp<AaptFile>& in,