Bug 1690790 - Add a SM(p) Linux32 job. r=sfink,jmaher

We don't run JS shell tests on 32-bit x86 anywhere (as tier 1) now that the Win32
jobs are tier 2. The Win32 jobs were also really slow. This has resulted in regressions
not being caught in CI (see bug 1335652 for example).

This patch adds a plaindebug job for Linux32. It catches the current jit-test
bustage from bug 1335652 on a Try push.

The patch fixes autospider.py to ensure use_minidump is always false for
cross-compiled 32-bit builds on Linux64.

Differential Revision: https://phabricator.services.mozilla.com/D104068

js/src/devtools/automation/autospider.py

@@ -446,7 +446,7 @@ for k, v in variant.get("env", {}).items():
 
 if AUTOMATION:
     # Currently only supported on linux64.
-    if platform.system() == "Linux" and platform.machine() == "x86_64":
+    if platform.system() == "Linux" and word_bits == 64:
         use_minidump = variant.get("use_minidump", True)
     else:
         use_minidump = False

js/src/devtools/automation/variants/arm-sim

@@ -2,6 +2,5 @@
     "configure-args": "--enable-simulator=arm --target=i686-pc-linux --enable-rust-simd",
     "optimize": true,
     "debug": true,
-    "bits": 32,
-    "use_minidump": false
+    "bits": 32
 }

taskcluster/ci/config.yml

@@ -207,6 +207,7 @@ try:
     # all"
     ridealong-builds:
         'linux':
+            - 'sm-plain-linux32'
             - 'sm-arm-sim-linux32'
         'linux64':
             - 'sm-plain-linux64'

taskcluster/ci/spidermonkey/linux.yml

@@ -118,6 +118,19 @@ sm-nojit-linux64/opt:
     run:
         spidermonkey-variant: nojit
 
+sm-plain-linux32/debug:
+    description: "Spidermonkey Plain"
+    index:
+        job-name: sm-plain-linux32-debug
+    treeherder:
+        platform: linux32/debug
+        symbol: SM(p)
+    worker:
+        docker-image: {in-tree: debian8-i386-build}
+    run:
+        spidermonkey-variant: plaindebug
+        spidermonkey-platform: linux
+
 sm-arm-sim-linux32/debug:
     description: "Spidermonkey ARM sim"
     index: