Fuchsia: Reland enable observatory. Pass rpath for host builds.

runtime/bin/BUILD.gn

 # Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
 # for details. All rights reserved. Use of this source code is governed by a
 # BSD-style license that can be found in the LICENSE file.
 
 import("gypi_contents.gni")
 
 declare_args() {
   # Whether to fall back to built-in root certificates when they cannot be
   # verified at the operating system level.
   dart_use_fallback_root_certificates = false
@@ skipping 546 matching lines @@
   extra_sources = []
   if (defined(invoker.extra_sources)) {
     extra_sources += invoker.extra_sources
   }
   executable(target_name) {
     configs += [
                  "..:dart_config",
                  "..:dart_maybe_product_config",
                ] + extra_configs
 
+    if (defined(is_fuchsia_host) && is_fuchsia_host) {
+      # We already have these in the standalone build, but Fuchsia doesn't
+      # have them. They are needed for running Fuchsia binaries built for the
+      # host.
+      if (is_linux) {
+        configs += [ "../../build/config/gcc:executable_ldconfig" ]
+      } else if (is_mac) {
+        configs += [ "../../build/config/mac:mac_dynamic_flags" ]
+      }
+    }
+
     deps = [
              ":gen_resources_cc",
              ":standalone_dart_io",
              ":libdart_builtin",
              "$dart_zlib_path",
            ] + extra_deps
 
     if (dart_use_tcmalloc) {
       deps += [ "//third_party/tcmalloc" ]
     }
@@ skipping 23 matching lines @@
         "iphlpapi.lib",
         "psapi.lib",
         "ws2_32.lib",
         "Rpcrt4.lib",
         "winmm.lib",
       ]
     }
   }
 }
 
-if (!defined(is_fuchsia) || !is_fuchsia) {
-  dart_executable("dart") {
-    extra_deps = [
-      "..:libdart",
-      ":dart_snapshot_cc",
-      "../observatory:standalone_observatory_archive",
-    ]
-    extra_sources = [ "builtin_nolib.cc" ]
-  }
+dart_executable("dart") {
+  extra_deps = [
+    "..:libdart",
+    ":dart_snapshot_cc",
+    "../observatory:standalone_observatory_archive",
+  ]
+  extra_sources = [ "builtin_nolib.cc" ]
+}
 
-  dart_executable("dart_noopt") {
-    extra_configs = [ "..:dart_precompiler_config" ]
-    extra_deps = [
-      "..:libdart_noopt",
-      ":dart_snapshot_cc",
-      "../observatory:standalone_observatory_archive",
-    ]
-    extra_sources = [ "builtin_nolib.cc" ]
-  }
+dart_executable("dart_noopt") {
+  extra_configs = [ "..:dart_precompiler_config" ]
+  extra_deps = [
+    "..:libdart_noopt",
+    ":dart_snapshot_cc",
+    "../observatory:standalone_observatory_archive",
+  ]
+  extra_sources = [ "builtin_nolib.cc" ]
+}
 
-  dart_executable("dart_precompiled_runtime") {
-    extra_configs = [ "..:dart_precompiled_runtime_config" ]
-    extra_deps = [
-      "..:libdart_precompiled_runtime",
-      "../observatory:standalone_observatory_archive",
-    ]
-    extra_sources = [
-      "builtin_nolib.cc",
-      "snapshot_empty.cc",
-    ]
-  }
+dart_executable("dart_precompiled_runtime") {
+  extra_configs = [ "..:dart_precompiled_runtime_config" ]
+  extra_deps = [
+    "..:libdart_precompiled_runtime",
+    "../observatory:standalone_observatory_archive",
+  ]
+  extra_sources = [
+    "builtin_nolib.cc",
+    "snapshot_empty.cc",
+  ]
 }
 
 dart_executable("dart_bootstrap") {
   extra_configs = [
     "..:dart_precompiler_config",
     "..:dart_no_snapshot_config",
   ]
   extra_deps = [
     ":generate_builtin_cc_file",
     ":generate_io_cc_file",
@@ skipping 198 matching lines @@
       # The only effect of DART_SHARED_LIB is to export the Dart API.
       "DART_SHARED_LIB",
     ]
     if (is_win) {
       libs = [ "dart.lib" ]
       abs_root_out_dir = rebase_path(root_out_dir)
       ldflags = [ "/LIBPATH:$abs_root_out_dir" ]
     }
   }
 }