Updated memory_replay description.

The description of memory_replay talks about unzippping the trace
files, but this is no longer necessary. This language has been
updated to reflect this.

Test: NA
Change-Id: Id808f9bd1286284c8de12b19c08eb8677c76dd53
diff --git a/docs/native_allocator.md b/docs/native_allocator.md
index 82a98fe..7695470 100644
--- a/docs/native_allocator.md
+++ b/docs/native_allocator.md
@@ -263,21 +263,22 @@
 To generate these traces, see the [Malloc Debug documentation](https://android.googlesource.com/platform/bionic/+/master/libc/malloc_debug/README.md),
 the option [record\_allocs](https://android.googlesource.com/platform/bionic/+/master/libc/malloc_debug/README.md#record_allocs_total_entries).
 
-To run these benchmarks, first copy the trace files to the target and
-unzip them using these commands:
+To run these benchmarks, first copy the trace files to the target using
+these commands:
 
     adb shell push system/extras/traces /data/local/tmp
-    adb shell 'cd /data/local/tmp/traces && for name in *.zip; do unzip $name; done'
 
 Since all of the traces come from applications, the `memory_replay` program
 will always call `mallopt(M_DECAY_TIME, 1)' before running the trace.
 
 Run the benchmark thusly:
 
-    adb shell memory_replay64 /data/local/tmp/traces/XXX.txt
-    adb shell memory_replay32 /data/local/tmp/traces/XXX.txt
+    adb shell memory_replay64 /data/local/tmp/traces/XXX.zip
+    adb shell memory_replay32 /data/local/tmp/traces/XXX.zip
 
-Where XXX.txt is the name of a trace file.
+Where XXX.zip is the name of a zipped trace file. The `memory_replay`
+program also can process text files, but all trace files are currently
+checked in as zip files.
 
 Every 100000 allocation operations, a dump of the RSS and VA space will be
 performed. At the end, a final RSS and VA space number will be printed.