Use -Werror in frameworks/base

* Fix unused variable and return value warnings.

Bug: 66996870
Test: build with WITH_TIDY=1
Change-Id: I890e65a20848d00559ba5a4f9691be1347b456af
diff --git a/tools/bit/main.cpp b/tools/bit/main.cpp
index d056ba5..ad23971 100644
--- a/tools/bit/main.cpp
+++ b/tools/bit/main.cpp
@@ -561,6 +561,15 @@
     }
 }
 
+static void
+chdir_or_exit(const char *path) {
+    // TODO: print_command("cd", path);
+    if (0 != chdir(path)) {
+        print_error("Error: Could not chdir: %s", path);
+        exit(1);
+    }
+}
+
 /**
  * Run the build, install, and test actions.
  */
@@ -583,8 +592,7 @@
     const string buildId = get_build_var(buildTop, "BUILD_ID", false);
     const string buildOut = get_out_dir();
 
-    // TODO: print_command("cd", buildTop.c_str());
-    chdir(buildTop.c_str());
+    chdir_or_exit(buildTop.c_str());
 
     // Get the modules for the targets
     map<string,Module> modules;
@@ -952,7 +960,7 @@
     const string buildProduct = get_required_env("TARGET_PRODUCT", false);
     const string buildOut = get_out_dir();
 
-    chdir(buildTop.c_str());
+    chdir_or_exit(buildTop.c_str());
 
     string buildDevice = sniff_device_name(buildOut, buildProduct);