[minor] Change expression evaluation cli argument to -Xexpression

compiler/cli/cli-common/src/org/jetbrains/kotlin/cli/common/arguments/K2JVMCompilerArguments.kt

@@ -49,7 +49,7 @@ class K2JVMCompilerArguments : CommonCompilerArguments() {
     @Argument(value = "-no-reflect", description = "Don't automatically include Kotlin reflection into the classpath")
     var noReflect: Boolean by FreezableVar(false)
 
-    @Argument(value = "-expression", description = "Evaluate the given string as a Kotlin script")
+    @Argument(value = "-Xexpression", description = "Evaluate the given string as a Kotlin script")
     var expressions: Array<String>? by FreezableVar(null)
 
     @Argument(

compiler/cli/cli-runner/src/org/jetbrains/kotlin/runner/runners.kt

@@ -152,7 +152,7 @@ class ExpressionRunner(private val code: List<String>) : RunnerWithCompiler() {
         val compilerArgs = ArrayList<String>().apply {
             addClasspathArgIfNeeded(classpath)
             code.forEach {
-                add("-expression")
+                add("-Xexpression")
                 add(it)
             }
             addAll(arguments)

compiler/testData/cli/jvm/extraHelp.out

@@ -18,6 +18,7 @@ where advanced options include:
                              'enable' since language version 1.3
   -Xdump-declarations-to=<path> Path to JSON file to dump Java to Kotlin declaration mappings
   -Xdisable-standard-script  Disable standard kotlin script support
+  -Xexpression               Evaluate the given string as a Kotlin script
   -Xfriend-paths=<path>      Paths to output directories for friend modules (whose internals should be visible)
   -Xmultifile-parts-inherit  Compile multifile classes as a hierarchy of parts and facade
   -Xir-check-local-names     Check that names of local classes and anonymous objects are the same in the IR backend as in the old backend

compiler/testData/cli/jvm/help.out

@@ -2,7 +2,6 @@ Usage: kotlinc-jvm <options> <source files>
 where possible options include:
   -classpath (-cp) <path>    List of directories and JAR/ZIP archives to search for user class files
   -d <directory|jar>         Destination for generated class files
-  -expression                Evaluate the given string as a Kotlin script
   -include-runtime           Include Kotlin runtime into the resulting JAR
   -java-parameters           Generate metadata for Java 1.8 reflection on method parameters
   -jdk-home <path>           Include a custom JDK from the specified location into the classpath instead of the default JAVA_HOME

plugins/scripting/scripting-compiler/tests/org/jetbrains/kotlin/scripting/compiler/plugin/ScriptingWithCliCompilerTest.kt

@@ -50,7 +50,7 @@ class ScriptingWithCliCompilerTest {
     fun testExpression() {
         runWithK2JVMCompiler(
             arrayOf(
-                "-expression",
+                "-Xexpression",
                 "val x = 7; println(x * 6); for (arg in args) println(arg)",
                 "--",
                 "hi",