Unify the three places that patch font loading for PDFium on Windows.

This also removed the code from content, which doesn't belong there because it's for a feature in Chrome.

In order to implement this in a unified way, I needed to create a public interface around ChildThread. A lot of the change is updating callers of ChildThread to use ChildThreadImpl instead.

BUG=448473

Review URL: https://codereview.chromium.org/897563002

Cr-Commit-Position: refs/heads/master@{#314367}

3 files changed, 17 insertions, 67 deletions

diff --git a/content/ppapi_plugin/ppapi_blink_platform_impl.cc b/content/ppapi_plugin/ppapi_blink_platform_impl.cc
index ad84196..793f6d6 100644
--- a/content/ppapi_plugin/ppapi_blink_platform_impl.cc
+++ b/content/ppapi_plugin/ppapi_blink_platform_impl.cc
@@ -10,7 +10,7 @@
 #include "base/strings/string16.h"
 #include "base/threading/platform_thread.h"
 #include "build/build_config.h"
-#include "content/child/child_thread.h"
+#include "content/child/child_thread_impl.h"
 #include "content/common/child_process_messages.h"
 #include "ppapi/proxy/plugin_globals.h"
 #include "ppapi/shared_impl/proxy_lock.h"
diff --git a/content/ppapi_plugin/ppapi_thread.cc b/content/ppapi_plugin/ppapi_thread.cc
index 6d77afe..103a7b8 100644
--- a/content/ppapi_plugin/ppapi_thread.cc
+++ b/content/ppapi_plugin/ppapi_thread.cc
@@ -42,12 +42,10 @@
 #include "ppapi/proxy/plugin_message_filter.h"
 #include "ppapi/proxy/ppapi_messages.h"
 #include "ppapi/proxy/resource_reply_thread_registrar.h"
-#include "ppapi/shared_impl/proxy_lock.h"
 #include "third_party/WebKit/public/web/WebKit.h"
 #include "ui/base/ui_base_switches.h"
 
 #if defined(OS_WIN)
-#include "base/win/iat_patch_function.h"
 #include "base/win/win_util.h"
 #include "base/win/windows_version.h"
 #include "sandbox/win/src/sandbox.h"
@@ -94,54 +92,6 @@ static void WarmupWindowsLocales(const ppapi::PpapiPermissions& permissions) {
   }
 }
 
-// TODO(scottmg): http://crbug.com/448473. This code should be removed from the
-// renderer once PDF is always OOP and/or PDF is made to use Skia instead of GDI
-// directly.
-const wchar_t kPdfFileName[] = L"pdf.dll";
-
-static base::win::IATPatchFunction g_iat_patch_createdca;
-HDC WINAPI CreateDCAPatch(LPCSTR driver_name,
-                          LPCSTR device_name,
-                          LPCSTR output,
-                          const void* init_data) {
-  DCHECK(std::string("DISPLAY") == std::string(driver_name));
-  DCHECK(!device_name);
-  DCHECK(!output);
-  DCHECK(!init_data);
-
-  // CreateDC fails behind the sandbox, but not CreateCompatibleDC.
-  return CreateCompatibleDC(NULL);
-}
-
-static base::win::IATPatchFunction g_iat_patch_get_font_data;
-DWORD WINAPI GetFontDataPatch(HDC hdc,
-                              DWORD table,
-                              DWORD offset,
-                              LPVOID buffer,
-                              DWORD length) {
-  int rv = GetFontData(hdc, table, offset, buffer, length);
-  if (rv == GDI_ERROR && hdc) {
-    HFONT font = static_cast<HFONT>(GetCurrentObject(hdc, OBJ_FONT));
-
-    LOGFONT logfont;
-    if (GetObject(font, sizeof(LOGFONT), &logfont)) {
-      std::vector<char> font_data;
-      {
-        ppapi::ProxyAutoLock lock;
-        // In the sandbox, font loading will fail. We ask the browser to load it
-        // which causes it to be loaded by the kernel, which then makes the
-        // subsequent call succeed.
-        ppapi::proxy::PluginGlobals::Get()->PreCacheFontForFlash(
-            reinterpret_cast<const void*>(&logfont));
-      }
-      rv = GetFontData(hdc, table, offset, buffer, length);
-    }
-  }
-  return rv;
-}
-
-#else
-extern void* g_target_services;
 #endif
 
 namespace content {
@@ -173,7 +123,7 @@ PpapiThread::~PpapiThread() {
 }
 
 void PpapiThread::Shutdown() {
-  ChildThread::Shutdown();
+  ChildThreadImpl::Shutdown();
 
   ppapi::proxy::PluginGlobals::Get()->ResetPluginProxyDelegate();
   if (plugin_entry_points_.shutdown_module)
@@ -185,7 +135,7 @@ void PpapiThread::Shutdown() {
 bool PpapiThread::Send(IPC::Message* msg) {
   // Allow access from multiple threads.
   if (base::MessageLoop::current() == message_loop())
-    return ChildThread::Send(msg);
+    return ChildThreadImpl::Send(msg);
 
   return sync_message_filter()->Send(msg);
 }
@@ -207,7 +157,7 @@ bool PpapiThread::OnControlMessageReceived(const IPC::Message& msg) {
 }
 
 void PpapiThread::OnChannelConnected(int32 peer_pid) {
-  ChildThread::OnChannelConnected(peer_pid);
+  ChildThreadImpl::OnChannelConnected(peer_pid);
 #if defined(OS_WIN)
   if (is_broker_)
     peer_handle_.Set(::OpenProcess(PROCESS_DUP_HANDLE, FALSE, peer_pid));
@@ -253,8 +203,7 @@ std::string PpapiThread::GetUILanguage() {
 
 void PpapiThread::PreCacheFont(const void* logfontw) {
 #if defined(OS_WIN)
-  Send(new ChildProcessHostMsg_PreCacheFont(
-      *static_cast<const LOGFONTW*>(logfontw)));
+  ChildThreadImpl::PreCacheFont(*static_cast<const LOGFONTW*>(logfontw));
 #endif
 }
 
@@ -374,15 +323,6 @@ void PpapiThread::OnLoadPlugin(const base::FilePath& path,
   // otherwise these would be silent terminations and fly under the radar).
   base::win::SetAbortBehaviorForCrashReporting();
 
-  // Need to patch a few functions for font loading to work correctly. This can
-  // be removed once we switch PDF to use Skia.
-  if (GetModuleHandle(kPdfFileName)) {
-    g_iat_patch_createdca.Patch(kPdfFileName, "gdi32.dll", "CreateDCA",
-                                CreateDCAPatch);
-    g_iat_patch_get_font_data.Patch(kPdfFileName, "gdi32.dll", "GetFontData",
-                                    GetFontDataPatch);
-  }
-
   // Once we lower the token the sandbox is locked down and no new modules
   // can be loaded. TODO(cpu): consider changing to the loading style of
   // regular plugins.
diff --git a/content/ppapi_plugin/ppapi_thread.h b/content/ppapi_plugin/ppapi_thread.h
index 3d80e49..8b4f522 100644
--- a/content/ppapi_plugin/ppapi_thread.h
+++ b/content/ppapi_plugin/ppapi_thread.h
@@ -14,7 +14,7 @@
 #include "base/process/process.h"
 #include "base/scoped_native_library.h"
 #include "build/build_config.h"
-#include "content/child/child_thread.h"
+#include "content/child/child_thread_impl.h"
 #include "content/public/common/pepper_plugin_info.h"
 #include "ppapi/c/pp_module.h"
 #include "ppapi/c/trusted/ppp_broker.h"
@@ -40,7 +40,13 @@ namespace content {
 
 class PpapiBlinkPlatformImpl;
 
-class PpapiThread : public ChildThread,
+#if defined(COMPILER_MSVC)
+// See explanation for other RenderViewHostImpl which is the same issue.
+#pragma warning(push)
+#pragma warning(disable: 4250)
+#endif
+
+class PpapiThread : public ChildThreadImpl,
                     public ppapi::proxy::PluginDispatcher::PluginDelegate,
                     public ppapi::proxy::PluginProxyDelegate {
  public:
@@ -158,6 +164,10 @@ class PpapiThread : public ChildThread,
   DISALLOW_IMPLICIT_CONSTRUCTORS(PpapiThread);
 };
 
+#if defined(COMPILER_MSVC)
+#pragma warning(pop)
+#endif
+
 }  // namespace content
 
 #endif  // CONTENT_PPAPI_PLUGIN_PPAPI_THREAD_H_