Bundle //ios/web resources in web shell

Upcoming work that will embed Service Manager in //ios/web will add
usage of //ios/web/resources; I will test this embedding via an EG
test that exercises web_shell and thus will need web_shell to bundle
these resources.

Bug: 731588
Change-Id: I1767d02ab13f6960811d80f516cc807f6ad486a1
Reviewed-on: https://chromium-review.googlesource.com/544310Reviewed-by: Sylvain Defresne <sdefresne@chromium.org>
Commit-Queue: Colin Blundell <blundell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#481887}

ios/web/shell/BUILD.gn

@@ -4,6 +4,7 @@
 
 import("//build/config/ios/rules.gni")
 import("//ios/build/config.gni")
+import("//tools/grit/repack.gni")
 
 ios_app_bundle("ios_web_shell") {
   info_plist = "Info.plist"
@@ -34,6 +35,18 @@ bundle_data("shell_bundle_data") {
   ]
 }
 
+repack("packed_resources") {
+  visibility = [ ":shell" ]
+  sources = [
+    "$root_gen_dir/ios/web/ios_web_resources.pak",
+  ]
+  deps = [
+    "//ios/web:resources",
+  ]
+  output = "$target_gen_dir/web_shell_resources.pak"
+  copy_data_to_bundle = true
+}
+
 source_set("shell") {
   sources = [
     "app_delegate.h",
@@ -56,6 +69,7 @@ source_set("shell") {
   ]
 
   deps = [
+    ":packed_resources",
     ":shell_bundle_data",
     "//base",
     "//ios/net",

ios/web/shell/shell_web_client.h

@@ -24,6 +24,10 @@ class ShellWebClient : public WebClient {
   std::unique_ptr<WebMainParts> CreateWebMainParts() override;
   std::string GetProduct() const override;
   std::string GetUserAgent(UserAgentType type) const override;
+  base::StringPiece GetDataResource(
+      int resource_id,
+      ui::ScaleFactor scale_factor) const override;
+  base::RefCountedMemory* GetDataResourceBytes(int resource_id) const override;
   void AllowCertificateError(
       WebState* web_state,
       int cert_error,

ios/web/shell/shell_web_client.mm

@@ -9,6 +9,7 @@
 #include "base/memory/ptr_util.h"
 #include "ios/web/public/user_agent.h"
 #include "ios/web/shell/shell_web_main_parts.h"
+#include "ui/base/resource/resource_bundle.h"
 
 #if !defined(__has_feature) || !__has_feature(objc_arc)
 #error "This file requires ARC support."
@@ -41,6 +42,18 @@ std::string ShellWebClient::GetUserAgent(UserAgentType type) const {
   return web::BuildUserAgentFromProduct(product);
 }
 
+base::StringPiece ShellWebClient::GetDataResource(
+    int resource_id,
+    ui::ScaleFactor scale_factor) const {
+  return ResourceBundle::GetSharedInstance().GetRawDataResourceForScale(
+      resource_id, scale_factor);
+}
+
+base::RefCountedMemory* ShellWebClient::GetDataResourceBytes(
+    int resource_id) const {
+  return ResourceBundle::GetSharedInstance().LoadDataResourceBytes(resource_id);
+}
+
 void ShellWebClient::AllowCertificateError(
     WebState*,
     int /*cert_error*/,

ios/web/shell/shell_web_main_parts.h

@@ -22,6 +22,7 @@ class ShellWebMainParts : public WebMainParts {
   ShellBrowserState* browser_state() const { return browser_state_.get(); }
 
   // WebMainParts implementation.
+  void PreMainMessageLoopStart() override;
   void PreMainMessageLoopRun() override;
 
  private:

ios/web/shell/shell_web_main_parts.mm

@@ -4,7 +4,9 @@
 
 #include "ios/web/shell/shell_web_main_parts.h"
 
+#include "base/path_service.h"
 #include "ios/web/shell/shell_browser_state.h"
+#include "ui/base/resource/resource_bundle.h"
 
 #if !defined(__has_feature) || !__has_feature(objc_arc)
 #error "This file requires ARC support."
@@ -18,6 +20,13 @@ ShellWebMainParts::ShellWebMainParts() {
 ShellWebMainParts::~ShellWebMainParts() {
 }
 
+void ShellWebMainParts::PreMainMessageLoopStart() {
+  base::FilePath pak_path;
+  PathService::Get(base::DIR_MODULE, &pak_path);
+  ui::ResourceBundle::InitSharedInstanceWithPakPath(
+      pak_path.AppendASCII("web_shell_resources.pak"));
+}
+
 void ShellWebMainParts::PreMainMessageLoopRun() {
   browser_state_.reset(new ShellBrowserState);
 }