depot_tools: add infra_paths recipe module for infra-specific paths

recipe_modules/git/example.expected/remote_not_origin.json

Index: recipe_modules/git/example.expected/remote_not_origin.json
diff --git a/recipe_modules/git/example.expected/remote_not_origin.json b/recipe_modules/git/example.expected/remote_not_origin.json
index f1b6f2eb60151e109b07f1ee75017fad9cb01817..6626ccbad027c9f96ef05498cbc5347ab2e90a3e 100644
--- a/recipe_modules/git/example.expected/remote_not_origin.json
+++ b/recipe_modules/git/example.expected/remote_not_origin.json
@@ -5,13 +5,12 @@
       "-u",
       "RECIPE_MODULE[depot_tools::git]/resources/git_setup.py",
       "--path",
-      "[SLAVE_BUILD]/src",
+      "[CWD]/src",
       "--url",
       "https://chromium.googlesource.com/chromium/src.git",
       "--remote",
       "not_origin"
     ],
-    "cwd": "[SLAVE_BUILD]",
     "name": "git setup"
   },
   {
@@ -23,7 +22,7 @@
       "master",
       "--recurse-submodules"
     ],
-    "cwd": "[SLAVE_BUILD]/src",
+    "cwd": "[CWD]/src",
     "name": "git fetch"
   },
   {
@@ -33,7 +32,7 @@
       "-f",
       "FETCH_HEAD"
     ],
-    "cwd": "[SLAVE_BUILD]/src",
+    "cwd": "[CWD]/src",
     "name": "git checkout"
   },
   {
@@ -42,7 +41,7 @@
       "rev-parse",
       "HEAD"
     ],
-    "cwd": "[SLAVE_BUILD]/src",
+    "cwd": "[CWD]/src",
     "name": "read revision",
     "stdout": "/path/to/tmp/",
     "~followup_annotations": [
@@ -57,7 +56,7 @@
       "-d",
       "-x"
     ],
-    "cwd": "[SLAVE_BUILD]/src",
+    "cwd": "[CWD]/src",
     "name": "git clean"
   },
   {
@@ -66,7 +65,7 @@
       "submodule",
       "sync"
     ],
-    "cwd": "[SLAVE_BUILD]/src",
+    "cwd": "[CWD]/src",
     "name": "submodule sync"
   },
   {
@@ -77,7 +76,7 @@
       "--init",
       "--recursive"
     ],
-    "cwd": "[SLAVE_BUILD]/src",
+    "cwd": "[CWD]/src",
     "name": "submodule update"
   },
   {
@@ -88,7 +87,7 @@
       "count-objects",
       "-v"
     ],
-    "cwd": "[SLAVE_BUILD]/src",
+    "cwd": "[CWD]/src",
     "name": "count-objects",
     "stdout": "/path/to/tmp/"
   },
@@ -99,7 +98,7 @@
       "--get",
       "remote.origin.url"
     ],
-    "cwd": "[SLAVE_BUILD]/src",
+    "cwd": "[CWD]/src",
     "name": "git config remote.origin.url",
     "stdout": "/path/to/tmp/",
     "~followup_annotations": [
@@ -114,7 +113,7 @@
       "--format=%at",
       "-s"
     ],
-    "cwd": "[SLAVE_BUILD]/src",
+    "cwd": "[CWD]/src",
     "name": "git show",
     "stdout": "/path/to/tmp/"
   },
@@ -125,7 +124,7 @@
       "not_origin",
       "--tags"
     ],
-    "cwd": "[SLAVE_BUILD]/src",
+    "cwd": "[CWD]/src",
     "name": "git fetch tags"
   },
   {
@@ -133,7 +132,7 @@
       "git",
       "status"
     ],
-    "cwd": "[SLAVE_BUILD]/src",
+    "cwd": "[CWD]/src",
     "name": "git status"
   },
   {
@@ -141,7 +140,7 @@
       "git",
       "status"
     ],
-    "cwd": "[SLAVE_BUILD]/src",
+    "cwd": "[CWD]/src",
     "name": "git status can_fail_build"
   },
   {
@@ -149,7 +148,7 @@
       "git",
       "status"
     ],
-    "cwd": "[SLAVE_BUILD]/src",
+    "cwd": "[CWD]/src",
     "name": "git status cannot_fail_build"
   },
   {
@@ -158,7 +157,7 @@
       "rebase",
       "not_origin/master"
     ],
-    "cwd": "[SLAVE_BUILD]/src",
+    "cwd": "[CWD]/src",
     "name": "my repo rebase"
   },
   {
@@ -166,10 +165,10 @@
       "git",
       "bundle",
       "create",
-      "[SLAVE_BUILD]/all.bundle",
+      "[CWD]/all.bundle",
       "--all"
     ],
-    "cwd": "[SLAVE_BUILD]/src",
+    "cwd": "[CWD]/src",
     "name": "git bundle"
   },
   {