Fence didn't manager sync_wait error codes properly

error codes are returned in errno, this caused ::waitForwever()
to only wait for 1 second and return improper error code (-1).

needed to help debugging 7316632

Bug: 7316632
Change-Id: Ie144f614a88393393972a3a770c6b4b0581f961a
diff --git a/include/ui/Fence.h b/include/ui/Fence.h
index a8460c2..ff6cefe 100644
--- a/include/ui/Fence.h
+++ b/include/ui/Fence.h
@@ -60,14 +60,14 @@
     // before the fence signals then -ETIME is returned.  A timeout of
     // TIMEOUT_NEVER may be used to indicate that the call should wait
     // indefinitely for the fence to signal.
-    int wait(unsigned int timeout);
+    status_t wait(unsigned int timeout);
 
     // waitForever is a convenience function for waiting forever for a fence to
     // signal (just like wait(TIMEOUT_NEVER)), but issuing an error to the
     // system log and fence state to the kernel log if the wait lasts longer
     // than warningTimeout. The logname argument should be a string identifying
     // the caller and will be included in the log message.
-    int waitForever(unsigned int warningTimeout, const char* logname);
+    status_t waitForever(unsigned int warningTimeout, const char* logname);
 
     // TIMEOUT_NEVER may be passed to the wait method to indicate that it
     // should wait indefinitely for the fence to signal.