Add tests using older agp versions

(cherry picked from commit be3fd36)

Author: hfmehmed

integration-tests/build.gradle.kts

@@ -38,7 +38,8 @@ fun Test.configureCommonSettings() {
 }
 
 val agpCompatibilityTestClasses = listOf(
-    "**/AGP812IT.class", "**/AGP810IT.class", "**/AGP890IT.class", "**/AGP900IT.class", "**/BuiltInKotlinAGP900IT.class"
+    "**/AGP812IT.class", "**/AGP810IT.class", "**/AGP880IT.class", "**/AGP870IT.class", "**/AGP890IT.class",
+    "**/AGP900IT.class", "**/BuiltInKotlinAGP900IT.class"
 )
 
 // Create a new test task for the AGP compatibility tests

integration-tests/src/test/kotlin/com/google/devtools/ksp/test/AGP870IT.kt

@@ -0,0 +1,25 @@
+package com.google.devtools.ksp.test
+
+import com.google.devtools.ksp.test.fixtures.TemporaryTestProject
+import org.gradle.testkit.runner.GradleRunner
+import org.gradle.testkit.runner.TaskOutcome
+import org.junit.Assert
+import org.junit.Rule
+import org.junit.Test
+import java.io.File
+
+class AGP870IT {
+    @Rule
+    @JvmField
+    val project: TemporaryTestProject = TemporaryTestProject("playground-android-multi", "playground")
+
+    @Test
+    fun testRunsKSP() {
+        val gradleRunner = GradleRunner.create().withProjectDir(project.root).withGradleVersion("8.11.1")
+
+        File(project.root, "gradle.properties").appendText("\nagpVersion=8.7.0")
+        gradleRunner.withArguments(":workload:compileDebugKotlin").build().let { result ->
+            Assert.assertEquals(TaskOutcome.SUCCESS, result.task(":workload:kspDebugKotlin")?.outcome)
+        }
+    }
+}

integration-tests/src/test/kotlin/com/google/devtools/ksp/test/AGP880IT.kt

@@ -0,0 +1,25 @@
+package com.google.devtools.ksp.test
+
+import com.google.devtools.ksp.test.fixtures.TemporaryTestProject
+import org.gradle.testkit.runner.GradleRunner
+import org.gradle.testkit.runner.TaskOutcome
+import org.junit.Assert
+import org.junit.Rule
+import org.junit.Test
+import java.io.File
+
+class AGP880IT {
+    @Rule
+    @JvmField
+    val project: TemporaryTestProject = TemporaryTestProject("playground-android-multi", "playground")
+
+    @Test
+    fun testRunsKSP() {
+        val gradleRunner = GradleRunner.create().withProjectDir(project.root).withGradleVersion("8.11.1")
+
+        File(project.root, "gradle.properties").appendText("\nagpVersion=8.8.0")
+        gradleRunner.withArguments(":workload:compileDebugKotlin").build().let { result ->
+            Assert.assertEquals(TaskOutcome.SUCCESS, result.task(":workload:kspDebugKotlin")?.outcome)
+        }
+    }
+}