libprocessgroup: Allow vendor profile attributes to override system ones

In the current implementation vendor profile attributes do not override
system ones and instead generate a warning. Fix that by overriding existing
attribute if a new definition is found.

Bug: 160318642
Test: add vendor attributes and confirm no warnings
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Change-Id: I71a2ee4d4b3c585e7c9a01b791e973390d409cbc
diff --git a/libprocessgroup/task_profiles.h b/libprocessgroup/task_profiles.h
index 28bc00c..2983a09 100644
--- a/libprocessgroup/task_profiles.h
+++ b/libprocessgroup/task_profiles.h
@@ -33,6 +33,7 @@
 
     const CgroupController* controller() const { return &controller_; }
     const std::string& file_name() const { return file_name_; }
+    void Reset(const CgroupController& controller, const std::string& file_name);
 
     bool GetPathForTask(int tid, std::string* path) const;