Merge changes I316c13e3,I4d99744d,Id9614b72,I7c98a0b7

* changes:
  init: enable error reporting of builtin functions
  init: log Service failures via Result<T>
  init: pass errors from one Result<T> to another better
  init: cleanup environment handling
diff --git a/fastboot/fastboot.cpp b/fastboot/fastboot.cpp
index 49d9438..5f2267c 100644
--- a/fastboot/fastboot.cpp
+++ b/fastboot/fastboot.cpp
@@ -1463,7 +1463,7 @@
 
     if (fs_generator_generate(gen, output.path, size, initial_dir,
             eraseBlkSize, logicalBlkSize)) {
-        fprintf(stderr, "Cannot generate image: %s\n", strerror(errno));
+        die("Cannot generate image for %s\n", partition);
         return;
     }