[build] Enable downloading mips toolchain via runhooks

This downloads the mips tool chain into tools/mips_toolchain via
runhooks if the flag download_mips_toolchain is specified for
gclient.

The currently uploaded version is 2015/1/7.

Bug: chromium:632390
Change-Id: Ied396d1a980db962773a96e9dadd3f282c7541c0
Reviewed-on: https://chromium-review.googlesource.com/892864
Reviewed-by: Yang Guo <yangguo@chromium.org>
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#50999}

.gitignore

@@ -72,6 +72,8 @@
 /tools/jsfunfuzz/jsfunfuzz
 /tools/jsfunfuzz/jsfunfuzz.tar.gz
 /tools/luci-go
+/tools/mips_toolchain
+/tools/mips_toolchain.tar.gz
 /tools/oom_dump/oom_dump
 /tools/oom_dump/oom_dump.o
 /tools/swarming_client

DEPS

@@ -3,9 +3,10 @@
 # all paths in here must match this assumption.
 
 vars = {
+  'build_for_node': False,
   'checkout_instrumented_libraries': False,
   'chromium_url': 'https://chromium.googlesource.com',
-  'build_for_node': False,
+  'download_mips_toolchain': False,
 }
 
 deps = {
@@ -320,6 +321,19 @@ hooks = [
       'v8/build/fuchsia/update_sdk.py',
     ],
   },
+  {
+    'name': 'mips_toolchain',
+    'pattern': '.',
+    'condition': 'download_mips_toolchain',
+    'action': [ 'download_from_google_storage',
+                '--no_resume',
+                '--platform=linux',
+                '--no_auth',
+                '-u',
+                '--bucket', 'chromium-v8',
+                '-s', 'v8/tools/mips_toolchain.tar.gz.sha1',
+    ],
+  },
   {
     # A change to a .gyp, .gypi, or to GYP itself should run the generator.
     'name': 'regyp_if_needed',

tools/mips_toolchain.tar.gz.sha1

@@ -0,0 +1 @@
+d51b5d903340262d8d13ecd51054c16a901b3cf3