Add time and I/O info to last_install

One example of last_install is:

/sideload/package.zip
1
time_total: 101
bytes_written_system: 14574000
bytes_stashed_system: 100
bytes_written_vendor: 5107400
bytes_stashed_vendor: 0

Bug: 28658632
Change-Id: I4bf79ea71a609068d38fbce6b41bcb892524aa7a
diff --git a/updater/blockimg.cpp b/updater/blockimg.cpp
index c20bad9..d67af66 100644
--- a/updater/blockimg.cpp
+++ b/updater/blockimg.cpp
@@ -373,6 +373,7 @@
     bool isunresumable;
     int version;
     size_t written;
+    size_t stashed;
     NewThreadInfo nti;
     pthread_t thread;
     std::vector<uint8_t> buffer;
@@ -777,6 +778,7 @@
     }
 
     fprintf(stderr, "stashing %zu blocks to %s\n", blocks, id.c_str());
+    params.stashed += blocks;
     return WriteStash(base, id, blocks, buffer, false, nullptr);
 }
 
@@ -973,6 +975,7 @@
                 return -1;
             }
 
+            params.stashed += src_blocks;
             // Can be deleted when the write has completed
             if (!stash_exists) {
                 params.freestash = srchash;
@@ -1517,8 +1520,17 @@
         pthread_join(params.thread, nullptr);
 
         fprintf(stderr, "wrote %zu blocks; expected %d\n", params.written, total_blocks);
+        fprintf(stderr, "stashed %zu blocks\n", params.stashed);
         fprintf(stderr, "max alloc needed was %zu\n", params.buffer.size());
 
+        const char* partition = strrchr(blockdev_filename->data, '/');
+        if (partition != nullptr && *(partition+1) != 0) {
+            fprintf(cmd_pipe, "log bytes_written_%s: %zu\n", partition + 1,
+                    params.written * BLOCKSIZE);
+            fprintf(cmd_pipe, "log bytes_stashed_%s: %zu\n", partition + 1,
+                    params.stashed * BLOCKSIZE);
+            fflush(cmd_pipe);
+        }
         // Delete stash only after successfully completing the update, as it
         // may contain blocks needed to complete the update later.
         DeleteStash(params.stashbase);