Fix incorrectly configured IDE tests

The important changes are in ideaTestUtils.kt:
`configureByFiles` must be called on the relative to testData dir path,
otherwise java files in the project belong to src/idea/testData/.../A.java
instead of src/A.java and can't be found in the root package

New updates in resolution when resolving A() call is now asking whether
<root>.A exists in PsiPackage::getClasses instead of
PsiPackage::findClassByShortName that can find a class even if it's located
in the wrong directory

idea/idea-test-framework/src/org/jetbrains/kotlin/idea/test/KotlinLightPlatformCodeInsightFixtureTestCase.kt

@@ -22,6 +22,8 @@ import com.intellij.openapi.vfs.newvfs.impl.VfsRootAccess
 import com.intellij.testFramework.fixtures.LightPlatformCodeInsightFixtureTestCase
 import org.jetbrains.kotlin.idea.actions.internal.KotlinInternalMode
 import org.jetbrains.kotlin.test.KotlinTestUtils
+import org.jetbrains.kotlin.test.TestMetadata
+import kotlin.reflect.full.findAnnotation
 
 abstract class KotlinLightPlatformCodeInsightFixtureTestCase: LightPlatformCodeInsightFixtureTestCase() {
     private var kotlinInternalModeOriginalValue: Boolean = false
@@ -44,4 +46,6 @@ abstract class KotlinLightPlatformCodeInsightFixtureTestCase: LightPlatformCodeI
             super.tearDown()
         }
     }
-}
+
+    override fun getTestDataPath(): String = this::class.findAnnotation<TestMetadata>()?.value ?: super.getTestDataPath()
+}