Add host_info step to new android bots.

Noticed this was missing on all the new android bots.

BUG=

Review URL: https://codereview.chromium.org/1067923002

Cr-Commit-Position: refs/heads/master@{#324104}

testing/buildbot/chromium.perf.json

@@ -89,6 +89,10 @@
   },
   "Android Nexus6 Perf": {
     "scripts": [
+      {
+        "name": "host_info",
+        "script": "host_info.py"
+      },
       {
         "args": [
           "cc_perftests"
@@ -122,6 +126,10 @@
   },
   "Android Nexus9 Perf": {
     "scripts": [
+      {
+        "name": "host_info",
+        "script": "host_info.py"
+      },
       {
         "args": [
           "gpu_perftests"
@@ -139,7 +147,12 @@
     ]
   },
   "Android One Perf": {
-    "scripts": []
+    "scripts": [
+      {
+        "name": "host_info",
+        "script": "host_info.py"
+      }
+    ]
   },
   "Linux Perf (3)": {
     "scripts": [