Revert "[v8-platform] Store the platform in a unique_ptr"

This reverts commit 608e8dd6b87b15772862dca9b7b2e6791a25dab6.

Reason for revert: Breaks the roll into Chromium

pdf/pdfium/fuzzers/pdfium_fuzzer_helper.cc:238:5: error: no matching function for call to 'InitializeV8ForPDFium'
    InitializeV8ForPDFium(ProgramPath(), "", &natives_blob, &snapshot_blob,
    ^~~~~~~~~~~~~~~~~~~~~
../../third_party/pdfium/testing/test_support.h:94:31: note: candidate function not viable: requires 4 arguments, but 5 were provided
std::unique_ptr<v8::Platform> InitializeV8ForPDFium(
                              ^

https://logs.chromium.org/v/?s=chromium%2Fbb%2Ftryserver.chromium.linux%2Flinux_chromium_compile_dbg_ng%2F461077%2F%2B%2Frecipes%2Fsteps%2Fcompile__with_patch_%2F0%2Fstdout



Original change's description:
> [v8-platform] Store the platform in a unique_ptr
> 
> We want to change the signature of {CreateDefaultPlatform} in the V8
> API to return a unique_ptr instead of a raw pointer to indicate that the
> caller owns the platform. With this change we prepare pdfium for this
> change.
> 
> R=​thestig@chromium.org
> 
> Change-Id: I4a0a466dfc37b28387a91543623a7a481ca8035a
> Reviewed-on: https://pdfium-review.googlesource.com/18191
> Commit-Queue: Lei Zhang <thestig@chromium.org>
> Reviewed-by: Lei Zhang <thestig@chromium.org>

TBR=thestig@chromium.org,ahaas@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Change-Id: I418c97653e8aba93560537f0d41e1aaa238bf3b4
Reviewed-on: https://pdfium-review.googlesource.com/25850
Commit-Queue: dsinclair <dsinclair@chromium.org>
Reviewed-by: dsinclair <dsinclair@chromium.org>
diff --git a/testing/test_support.cpp b/testing/test_support.cpp
index 2b6f436..b32ec7d 100644
--- a/testing/test_support.cpp
+++ b/testing/test_support.cpp
@@ -60,18 +60,17 @@
 }
 #endif  // V8_USE_EXTERNAL_STARTUP_DATA
 
-std::unique_ptr<v8::Platform> InitializeV8Common(const std::string& exe_path) {
-  v8::V8::InitializeICUDefaultLocation(exe_path.c_str());
+void InitializeV8Common(const char* exe_path, v8::Platform** platform) {
+  v8::V8::InitializeICUDefaultLocation(exe_path);
 
-  std::unique_ptr<v8::Platform> platform = v8::platform::NewDefaultPlatform();
-  v8::V8::InitializePlatform(platform.get());
+  *platform = v8::platform::CreateDefaultPlatform();
+  v8::V8::InitializePlatform(*platform);
 
   // By enabling predictable mode, V8 won't post any background tasks.
   // By enabling GC, it makes it easier to chase use-after-free.
   const char v8_flags[] = "--predictable --expose-gc";
   v8::V8::SetFlagsFromString(v8_flags, static_cast<int>(strlen(v8_flags)));
   v8::V8::Initialize();
-  return platform;
 }
 #endif  // PDF_ENABLE_V8
 
@@ -178,26 +177,27 @@
 
 #ifdef PDF_ENABLE_V8
 #ifdef V8_USE_EXTERNAL_STARTUP_DATA
-std::unique_ptr<v8::Platform> InitializeV8ForPDFiumWithStartupData(
-    const std::string& exe_path,
-    const std::string& bin_dir,
-    v8::StartupData* natives_blob,
-    v8::StartupData* snapshot_blob) {
-  std::unique_ptr<v8::Platform> platform = InitializeV8Common(exe_path);
+bool InitializeV8ForPDFium(const std::string& exe_path,
+                           const std::string& bin_dir,
+                           v8::StartupData* natives_blob,
+                           v8::StartupData* snapshot_blob,
+                           v8::Platform** platform) {
+  InitializeV8Common(exe_path.c_str(), platform);
   if (natives_blob && snapshot_blob) {
     if (!GetExternalData(exe_path, bin_dir, "natives_blob.bin", natives_blob))
-      return nullptr;
+      return false;
     if (!GetExternalData(exe_path, bin_dir, "snapshot_blob.bin", snapshot_blob))
-      return nullptr;
+      return false;
     v8::V8::SetNativesDataBlob(natives_blob);
     v8::V8::SetSnapshotDataBlob(snapshot_blob);
   }
-  return platform;
+  return true;
 }
 #else   // V8_USE_EXTERNAL_STARTUP_DATA
-std::unique_ptr<v8::Platform> InitializeV8ForPDFium(
-    const std::string& exe_path) {
-  return InitializeV8Common(exe_path);
+bool InitializeV8ForPDFium(const std::string& exe_path,
+                           v8::Platform** platform) {
+  InitializeV8Common(exe_path.c_str(), platform);
+  return true;
 }
 #endif  // V8_USE_EXTERNAL_STARTUP_DATA
 #endif  // PDF_ENABLE_V8