Build: Use fake ideaHome for tests with intellij build number only

#KTI-82

buildSrc/src/main/kotlin/localDependencies.kt

@@ -113,4 +113,11 @@ object IntellijRootUtils {
     }
 }
 
-fun Project.intellijRootDir() = IntellijRootUtils.getIntellijRootDir(project)
+fun Project.ideaHomePathForTests() = rootProject.buildDir.resolve("ideaHomeForTests")
+
+fun Project.ideaBuildNumberFileForTests() = File(ideaHomePathForTests(), "build.txt")
+
+fun Project.writeIdeaBuildNumberForTests() {
+    ideaHomePathForTests().mkdirs()
+    ideaBuildNumberFileForTests().writeText("IC-${rootProject.extra["versions.intellijSdk"]}")
+}

buildSrc/src/main/kotlin/tasks.kt

@@ -110,6 +110,8 @@ fun Project.projectTest(
         evaluationDependsOn(":test-instrumenter")
     }
     return getOrCreateTask<Test>(taskName) {
+        dependsOn(":createIdeaHomeForTests")
+
         doFirst {
             if (jUnitMode == JUnitMode.JUnit5) return@doFirst
 
@@ -177,7 +179,7 @@ fun Project.projectTest(
 
         maxHeapSize = "1600m"
         systemProperty("idea.is.unit.test", "true")
-        systemProperty("idea.home.path", project.intellijRootDir().canonicalPath)
+        systemProperty("idea.home.path", project.ideaHomePathForTests().canonicalPath)
         systemProperty("java.awt.headless", "true")
         environment("NO_FS_ROOTS_ACCESS_CHECK", "true")
         environment("PROJECT_CLASSES_DIRS", project.testSourceSet.output.classesDirs.asPath)