Added CI step for building with validation layers (flutter#42724)

Let's try to make sure the validation layers don't break.

## Pre-launch Checklist

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Objective-C, Java style guides].
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above.
- [ ] I added new tests to check the change I am making or feature I am
adding, or Hixie said the PR is test-exempt. See [testing the engine]
for instructions on writing and running engine tests.
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- [x] All existing and new tests are passing.

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ci/builders/linux_android_debug_engine.json

@@ -134,6 +134,27 @@
                 ]
             }
         },
+        {
+            "cas_archive": false,
+            "drone_dimensions": [
+                "device_type=none",
+                "os=Linux"
+            ],
+            "gn": [
+                "--android",
+                "--android-cpu=arm64",
+                "--no-lto",
+                "--enable-vulkan-validation-layers"
+            ],
+            "name": "android_debug_arm64",
+            "ninja": {
+                "config": "android_debug_arm64",
+                "targets": [
+                    "flutter",
+                    "flutter/shell/platform/android:abi_jars"
+                ]
+            }
+        },
         {
             "archives": [
                 {