DropBoxManager: Allow adding a file using an fd

This patch adds an overload to DropBoxManager::addFile() which accepts
an already-opened file as a file descriptor. This avoids the need for
clients to create a filesystem-visible file when uploading data to
DropBox.

Test: Tested with perfetto using https://android-review.googlesource.com/c/platform/external/perfetto/+/587674
Change-Id: I076bfd3180fb9b4baff7e1bae2e611419061b2a7
Merged-In: I076bfd3180fb9b4baff7e1bae2e611419061b2a7
diff --git a/libs/services/src/os/DropBoxManager.cpp b/libs/services/src/os/DropBoxManager.cpp
index bbb45f0..e8e34d7 100644
--- a/libs/services/src/os/DropBoxManager.cpp
+++ b/libs/services/src/os/DropBoxManager.cpp
@@ -179,7 +179,12 @@
         ALOGW("DropboxManager: %s", message.c_str());
         return Status::fromExceptionCode(Status::EX_ILLEGAL_STATE, message.c_str());
     }
+    return addFile(tag, fd, flags);
+}
 
+Status
+DropBoxManager::addFile(const String16& tag, int fd, int flags)
+{
     Entry entry(tag, flags, fd);
     return add(entry);
 }