[unseasoned-pdf] Patch GetFontData() in renderers

Patches the GetFontData() call in all renderer processes to fix a crash
on Windows when trying to load the unseasoned PDF viewer. GetFontData()
was patched in PPAPI processes, but the unseasoned PDF viewer runs
inside a renderer process now.

Also renames MaybeInitializeGDI() to something less misleading.

Unfortunately, it's not possible to replicate this issue in a browser
test at this time; see crbug.com/1238982 for details.

Fixed: 1238982
Change-Id: Ifd5ad8c1d7820edd4f50807959029e25e10a7594
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3091845
Auto-Submit: K. Moon <kmoon@chromium.org>
Reviewed-by: Scott Violet <sky@chromium.org>
Reviewed-by: Will Harris <wfh@chromium.org>
Commit-Queue: K. Moon <kmoon@chromium.org>
Cr-Commit-Position: refs/heads/master@{#911565}

chrome/app/chrome_main_delegate.cc

@@ -1170,7 +1170,7 @@ void ChromeMainDelegate::PreSandboxStartup() {
   crash_keys::SetCrashKeysFromCommandLine(command_line);
 
 #if BUILDFLAG(ENABLE_PDF)
-  MaybeInitializeGDI();
+  MaybePatchGdiGetFontData();
 #endif
 }
 

chrome/child/pdf_child_init.cc

@@ -49,7 +49,7 @@ DWORD WINAPI GetFontDataPatch(HDC hdc,
 
 }  // namespace
 
-void MaybeInitializeGDI() {
+void MaybePatchGdiGetFontData() {
 #if defined(OS_WIN)
   // Only patch utility processes which explicitly need GDI.
   sandbox::policy::SandboxType service_sandbox_type =
@@ -59,6 +59,11 @@ void MaybeInitializeGDI() {
       service_sandbox_type == sandbox::policy::SandboxType::kPpapi ||
       service_sandbox_type == sandbox::policy::SandboxType::kPrintCompositor ||
       service_sandbox_type == sandbox::policy::SandboxType::kPdfConversion;
+
+  // TODO(crbug.com/1239330): Only apply to renderers containing PDF content.
+  if (service_sandbox_type == sandbox::policy::SandboxType::kRenderer)
+    need_gdi = true;
+
   if (!need_gdi)
     return;
 
@@ -69,8 +74,8 @@ void MaybeInitializeGDI() {
   HMODULE module = CURRENT_MODULE();
 #endif  // defined(COMPONENT_BUILD)
 
-  // Need to patch GetFontData() for font loading to work correctly. This can be
-  // removed once PDFium switches to use Skia. https://crbug.com/pdfium/11
+  // Need to patch GetFontData() for font loading to work correctly.
+  // TODO(crbug.com/pdfium/11): Can be removed once PDFium switches to use Skia.
   static base::NoDestructor<base::win::IATPatchFunction> patch_get_font_data;
   patch_get_font_data->PatchFromModule(
       module, "gdi32.dll", "GetFontData",

chrome/child/pdf_child_init.h

@@ -11,7 +11,7 @@
 #error "PDF must be enabled"
 #endif
 
-// Initializes child-process specific code for the PDF module.
-void MaybeInitializeGDI();
+// Possibly patches GDI's `GetFontData()` for use by PDFium.
+void MaybePatchGdiGetFontData();
 
 #endif  // CHROME_CHILD_PDF_CHILD_INIT_H_