Adds support for headless chrome embedder mojo services

headless/lib/browser/headless_browser_context_impl.cc

Index: headless/lib/browser/headless_browser_context_impl.cc
diff --git a/headless/lib/browser/headless_browser_context_impl.cc b/headless/lib/browser/headless_browser_context_impl.cc
index ed0188050ec88de09923d17faeab4fc65db6f886..87407e87e2e123dfaed525be1dffbf9a3e25a7b7 100644
--- a/headless/lib/browser/headless_browser_context_impl.cc
+++ b/headless/lib/browser/headless_browser_context_impl.cc
@@ -13,10 +13,15 @@
 #include "content/public/browser/storage_partition.h"
 #include "headless/lib/browser/headless_browser_impl.h"
 #include "headless/lib/browser/headless_url_request_context_getter.h"
+#include "headless/public/util/in_memory_protocol_handler.h"
 #include "net/url_request/url_request_context.h"
 
 namespace headless {
 
+namespace {
+const char kHeadlessMojomProtocol[] = "headless-mojom";
+}
+
 // Contains net::URLRequestContextGetter required for resource loading.
 // Must be destructed on the IO thread as per content::ResourceContext
 // requirements.
@@ -202,10 +207,42 @@ HeadlessBrowserContext::Builder::SetProtocolHandlers(
   return *this;
 }
 
+HeadlessBrowserContext::Builder&
+HeadlessBrowserContext::Builder::AddJsMojoBindings(
+    const std::string& mojom_name,
+    const std::string& js_bindings) {
+  mojo_bindings_.emplace_back(mojom_name, js_bindings);
+  return *this;
+}
+
 std::unique_ptr<HeadlessBrowserContext>
 HeadlessBrowserContext::Builder::Build() {
+  if (!mojo_bindings_.empty()) {
+    std::unique_ptr<InMemoryProtocolHandler> headless_mojom_protocol_handler(
+        new InMemoryProtocolHandler());
+    for (const MojoBindings& binding : mojo_bindings_) {
+      headless_mojom_protocol_handler->InsertResponse(
+          binding.mojom_name,
+          InMemoryProtocolHandler::Response(binding.js_bindings,
+                                            "application/javascript"));
+    }
+    DCHECK(protocol_handlers_.find(kHeadlessMojomProtocol) ==
+           protocol_handlers_.end());
+    protocol_handlers_[kHeadlessMojomProtocol] =
+        std::move(headless_mojom_protocol_handler);
+  }
+
   return base::WrapUnique(new HeadlessBrowserContextImpl(
       std::move(protocol_handlers_), browser_->options()));
 }
 
+HeadlessBrowserContext::Builder::MojoBindings::MojoBindings() {}
+
+HeadlessBrowserContext::Builder::MojoBindings::MojoBindings(
+    const std::string& mojom_name,
+    const std::string& js_bindings)
+    : mojom_name(mojom_name), js_bindings(js_bindings) {}
+
+HeadlessBrowserContext::Builder::MojoBindings::~MojoBindings() {}
+
 }  // namespace headless