ci: run instrumentation tests on Ubuntu with KVM and skip redundant runs

.github/workflows/coverage-history.yml

@@ -119,7 +119,7 @@ jobs:
           .github/scripts/push_coverage_history.sh 'chore: record unit coverage'
 
       # The emulator already ran on the pull request, so its artifact is reused
-      # instead of booting another macOS runner. It is usually still running at
+      # instead of booting another emulator. It is usually still running at
       # merge time, so wait for it rather than recording the commit as having
       # no instrumentation data at all.
       - name: Wait for the pull request's emulator run

.github/workflows/instrumentation-test.yml

@@ -20,18 +20,47 @@ on:
     types: [test]
   pull_request:
     branches-ignore: ['gh-pages']
+    types: [opened, synchronize, reopened, ready_for_review]
+    # Changes that cannot affect the emulator tests. Workflow changes still run, so a bumped
+    # action is exercised before it merges.
+    paths-ignore:
+      - '**.md'
+      - 'docs/**'
+      - '.gemini/**'
+      - 'LICENSE'
+      - '.github/ISSUE_TEMPLATE/**'
+      - '.github/CODEOWNERS'
+      - '.github/dependabot.yml'
   workflow_dispatch:
 
+# A new push to a pull request supersedes the run for the previous commit.
+concurrency:
+  group: ${{ github.workflow }}-${{ github.head_ref || github.ref }}
+  cancel-in-progress: true
+
 jobs:
   run-instrumentation-test:
-    runs-on: macOS-latest-large # enables hardware acceleration in the virtual machine
+    # Skip drafts (the run starts when the pull request is marked ready for review) and
+    # release-please pull requests, which only change versions and the changelog.
+    if: >-
+      github.event.pull_request.draft != true &&
+      !startsWith(github.head_ref, 'release-please--')
+    # Ubuntu runners support KVM, so the emulator runs with hardware acceleration on a standard
+    # runner instead of a billed macOS larger runner.
+    runs-on: ubuntu-latest
     permissions:
       pull-requests: write
     timeout-minutes: 45
     steps:
     - name: Checkout Repo
       uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
 
+    - name: Enable KVM
+      run: |
+        echo 'KERNEL=="kvm", GROUP="kvm", MODE="0666", OPTIONS+="static_node=kvm"' | sudo tee /etc/udev/rules.d/99-kvm4all.rules
+        sudo udevadm control --reload-rules
+        sudo udevadm trigger --name-match=kvm
+
     - name: Set up JDK 21
       uses: actions/setup-java@b6effb05e454b25005698d916606bdc6ffcbf961 # v5.7.0
       with:
@@ -55,7 +84,7 @@ jobs:
       with:
         api-level: 29
         target: google_apis
-        arch: x86
+        arch: x86_64
         disable-animations: true
         # The demo smoke tests run in their own workflow, see demo-smoke-test.yml.
         script: ./gradlew createDebugCoverageReport :maps-app:createLibraryCoverageReports --stacktrace -Pandroid.testInstrumentationRunnerArguments.notPackage=com.google.maps.android.compose.smoke