ART: dex2oat flag for HGraphVisualizer dump file

This patch adds a new flag to dex2oat which allows to specify the
name of the file that HGraphVisualizer will store its output into.
Until now the graph was dumped to "art.cfg" in the current working
directory. To make Checker work with run-test, the output directory
needs to be customizable.

Change-Id: I395c518b987e594e89e5e80f202a96befa41ac20
diff --git a/compiler/driver/compiler_driver.cc b/compiler/driver/compiler_driver.cc
index 9985d66..e371807 100644
--- a/compiler/driver/compiler_driver.cc
+++ b/compiler/driver/compiler_driver.cc
@@ -339,7 +339,8 @@
                                const InstructionSetFeatures* instruction_set_features,
                                bool image, std::set<std::string>* image_classes,
                                std::set<std::string>* compiled_classes, size_t thread_count,
-                               bool dump_stats, bool dump_passes, CumulativeLogger* timer,
+                               bool dump_stats, bool dump_passes,
+                               const std::string& dump_cfg_file_name, CumulativeLogger* timer,
                                int swap_fd, const std::string& profile_file)
     : swap_space_(swap_fd == -1 ? nullptr : new SwapSpace(swap_fd, 10 * MB)),
       swap_space_allocator_(new SwapAllocator<void>(swap_space_.get())),
@@ -361,6 +362,7 @@
       stats_(new AOTCompilationStats),
       dump_stats_(dump_stats),
       dump_passes_(dump_passes),
+      dump_cfg_file_name_(dump_cfg_file_name),
       timings_logger_(timer),
       compiler_context_(nullptr),
       support_boot_image_fixup_(instruction_set != kMips),