Fix test failure by reducing max shm size to 32 MB

Tests are failing on travis because the max allowed SHM size
was set to 2GB. Lowering down to 32 MB.
Also fixing the emulator scripts for mac.

Bug: 73625175
Change-Id: Ia6c3e6df38674c1e4a6723ae87589efe1605c257
diff --git a/tools/install-build-deps b/tools/install-build-deps
index b7c1fc8..434b93a 100755
--- a/tools/install-build-deps
+++ b/tools/install-build-deps
@@ -163,7 +163,7 @@
   ('buildtools/aosp-arm.zip',
    'https://storage.googleapis.com/perfetto/aosp-02022018-arm.zip',
    'a480d5e7d3ca888b0a58fe15ce76b1791537429a',
-   'linux2'
+   'all'
   ),
 
   # platform-tools.zip contains adb binaries.