Move 10% of ART run-tests to test group `presubmit` in `TEST_MAPPING`.

Move a few more ART run-tests from the `postsubmit` test group to the
`presubmit` test group. This progressive rollout is to make sure
introducing ART run-tests to this test group won't disturb/break
Android presubmits.

Output of `art/test/utils/regen-test-files`:

  $ art/test/utils/regen-test-files
  Generated Blueprint files for 616 ART run-tests ouf of 909 (67%).
  Generated TEST_MAPPING entries for 253 ART run-tests ouf of 909 (27%):
    25 tests (10%) in `presubmit` test group;
    228 tests (90%) in `postsubmit` test group.

Test: atest --test-mapping art:presubmit
Test: atest --test-mapping art:postsubmit
Bug: 152374989
Bug: 169310621
Change-Id: I3e401d0c441467b94390b678fccb0395263863c7
diff --git a/TEST_MAPPING b/TEST_MAPPING
index 2ee8581..66f5780 100644
--- a/TEST_MAPPING
+++ b/TEST_MAPPING
@@ -47,10 +47,7 @@
     },
     {
       "name": "art-run-test-014-math3"
-    }
-  ],
-  "postsubmit": [
-    // ART run-tests.
+    },
     {
       "name": "art-run-test-015-switch"
     },
@@ -89,7 +86,10 @@
     },
     {
       "name": "art-run-test-029-assert"
-    },
+    }
+  ],
+  "postsubmit": [
+    // ART run-tests.
     {
       "name": "art-run-test-033-class-init-deadlock"
     },
diff --git a/test/utils/regen-test-files b/test/utils/regen-test-files
index 1613bc5..c975416 100755
--- a/test/utils/regen-test-files
+++ b/test/utils/regen-test-files
@@ -280,7 +280,7 @@
 # the `presubmit` test group in `TEST_MAPPING` file -- the rest will be included
 # in `postsubmit` test group.
 # Currently, this value has to be a number between 1 and 99.
-presubmit_tests_percentage=5
+presubmit_tests_percentage=10
 
 cd "$ANDROID_BUILD_TOP/art"