Add generation of dependency file for .ap_ package

Make Aapt generate a dependency file in the same directory as the
output ap_ file if the --generate-dependencies flag is set.
This dependency file can then be read by the ant exec loop task
to see whether to repackage resources.

Change-Id: I763679414daf76369700aa599c26dcf78d4de099
diff --git a/tools/aapt/Resource.cpp b/tools/aapt/Resource.cpp
index a603314..6e86112 100644
--- a/tools/aapt/Resource.cpp
+++ b/tools/aapt/Resource.cpp
@@ -2187,15 +2187,26 @@
     return err;
 }
 
-status_t
-writeDependencyPreReqs(Bundle* bundle, const sp<AaptAssets>& assets, FILE* fp)
+// Loops through the string paths and writes them to the file pointer
+// Each file path is written on its own line with a terminating backslash.
+status_t writePathsToFile(const sp<FilePathStore>& files, FILE* fp)
 {
     status_t deps = -1;
-    sp<FilePathStore> files = assets->getFullResPaths();
     for (size_t file_i = 0; file_i < files->size(); ++file_i) {
         // Add the full file path to the dependency file
         fprintf(fp, "%s \\\n", files->itemAt(file_i).string());
         deps++;
     }
     return deps;
-}
\ No newline at end of file
+}
+
+status_t
+writeDependencyPreReqs(Bundle* bundle, const sp<AaptAssets>& assets, FILE* fp, bool includeRaw)
+{
+    status_t deps = -1;
+    deps += writePathsToFile(assets->getFullResPaths(), fp);
+    if (includeRaw) {
+        deps += writePathsToFile(assets->getFullAssetPaths(), fp);
+    }
+    return deps;
+}