[iOS/GN] Convert //ios/third_party/ochamcrest to build a framework.

build/config/BUILDCONFIG.gn

Index: build/config/BUILDCONFIG.gn
diff --git a/build/config/BUILDCONFIG.gn b/build/config/BUILDCONFIG.gn
index 2e7f8782ffe4e70fd67f18baa301c13105f3257f..c36aeabf7bdea75bce08525c09dd947818acb7ca 100644
--- a/build/config/BUILDCONFIG.gn
+++ b/build/config/BUILDCONFIG.gn
@@ -556,6 +556,16 @@ if (is_component_build) {
     }
   }
 }
+if (is_ios) {
+  set_defaults("ios_framework_bundle") {
+    configs = _shared_library_configs
+  }
+}
+if (is_mac) {
+  set_defaults("mac_framework_bundle") {
+    configs = _shared_library_configs
+  }
+}
 
 # Source set defaults (also for components in non-component mode).
 set_defaults("source_set") {