git: fix git cache support

recipe_modules/git/example.expected/git-cache-checkout.json

Index: recipe_modules/git/example.expected/git-cache-checkout.json
diff --git a/recipe_modules/git/example.expected/git-cache-checkout.json b/recipe_modules/git/example.expected/git-cache-checkout.json
index fb712ddce00bfac9c6ab9d3827b85fed591284f1..068c33d8bb12bbe22614267419f7ef14d90a4f29 100644
--- a/recipe_modules/git/example.expected/git-cache-checkout.json
+++ b/recipe_modules/git/example.expected/git-cache-checkout.json
@@ -16,15 +16,47 @@
       "git",
       "retry",
       "cache",
-      "fetch",
+      "populate",
       "-c",
-      "[GIT_CACHE]"
+      "[GIT_CACHE]",
+      "https://chromium.googlesource.com/chromium/src.git"
+    ],
+    "cwd": "[SLAVE_BUILD]/src",
+    "env": {
+      "PATH": "RECIPE_PACKAGE_REPO[depot_tools]:%(PATH)s"
+    },
+    "name": "populate cache"
+  },
+  {
+    "cmd": [
+      "git",
+      "cache",
+      "exists",
+      "--quiet",
+      "--cache-dir",
+      "[GIT_CACHE]",
+      "https://chromium.googlesource.com/chromium/src.git"
+    ],
+    "cwd": "[SLAVE_BUILD]/src",
+    "env": {
+      "PATH": "RECIPE_PACKAGE_REPO[depot_tools]:%(PATH)s"
+    },
+    "name": "git cache",
+    "stdout": "/path/to/tmp/"
+  },
+  {
+    "cmd": [
+      "git",
+      "remote",
+      "set-url",
+      "origin",
+      "mirror_dir"
     ],
     "cwd": "[SLAVE_BUILD]/src",
     "env": {
       "PATH": "RECIPE_PACKAGE_REPO[depot_tools]:%(PATH)s"
     },
-    "name": "fetch cache"
+    "name": "git remote"
   },
   {
     "cmd": [