Add explicit compiler option to enable test-specific features.

We can no longer rely on checking the "core.art" image name,
since we plan to remove it and use the shipped boot image.

This option enables test-specific features, such as $noinline$.

Test: ./art/test.py -r --optimizing --64
Bug: 147817558
Change-Id: Iadac6e1b0f46e83efd0551fb8462a6b268ad33d8
diff --git a/compiler/driver/compiler_options.cc b/compiler/driver/compiler_options.cc
index 5681134..0550075 100644
--- a/compiler/driver/compiler_options.cc
+++ b/compiler/driver/compiler_options.cc
@@ -51,7 +51,7 @@
       image_classes_(),
       verification_results_(nullptr),
       image_type_(ImageType::kNone),
-      compiling_with_core_image_(false),
+      compile_art_test_(false),
       baseline_(false),
       debuggable_(false),
       generate_debug_info_(kDefaultGenerateDebugInfo),
@@ -186,24 +186,4 @@
   return is_system_class;
 }
 
-bool CompilerOptions::IsCoreImageFilename(const std::string& boot_image_filename) {
-  std::string_view filename(boot_image_filename);
-  size_t colon_pos = filename.find(':');
-  if (colon_pos != std::string_view::npos) {
-    filename = filename.substr(0u, colon_pos);
-  }
-  // Look for "core.art" or "core-*.art".
-  if (EndsWith(filename, "core.art")) {
-    return true;
-  }
-  if (!EndsWith(filename, ".art")) {
-    return false;
-  }
-  size_t slash_pos = filename.rfind('/');
-  if (slash_pos == std::string::npos) {
-    return StartsWith(filename, "core-");
-  }
-  return filename.compare(slash_pos + 1, 5u, "core-") == 0;
-}
-
 }  // namespace art