[Mac/GN] Set up the component build.

build/secondary/third_party/crashpad/crashpad/handler/BUILD.gn

Index: build/secondary/third_party/crashpad/crashpad/handler/BUILD.gn
diff --git a/build/secondary/third_party/crashpad/crashpad/handler/BUILD.gn b/build/secondary/third_party/crashpad/crashpad/handler/BUILD.gn
index 0c455f50b5e0ef54c2a82b487c482651c5f1ba7e..56cbfb2096479bd6863f37f726d1eb7cb1e64bae 100644
--- a/build/secondary/third_party/crashpad/crashpad/handler/BUILD.gn
+++ b/build/secondary/third_party/crashpad/crashpad/handler/BUILD.gn
@@ -46,4 +46,13 @@ executable("crashpad_handler") {
     "//base",
     "//build/win:default_exe_manifest",
   ]
+
+  if (is_component_build) {
+    # The handler is in Chromium.app/Contents/Versions/X/Chromium Framework.framework/Helpers/

[Dirk Pranke, 2016/05/06 22:30:18]

I wonder if there's some automated way to get this via rebase_path() or some
other cleverness ...

+    # so set rpath up to the base.
+    ldflags = [
+      "-rpath",
+      "@loader_path/../../../../../..",
+    ]
+  }
 }