[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=egdaniel@google.com

Change-Id: Ib0bb743ca0acd98018cb28828890868f1e0fc612
Reviewed-on: https://skia-review.googlesource.com/69320
Reviewed-by: Greg Daniel <egdaniel@google.com>
Commit-Queue: Greg Daniel <egdaniel@google.com>
diff --git a/experimental/SkV8Example/SkV8Example.cpp b/experimental/SkV8Example/SkV8Example.cpp
index 5cad125..7d78f76 100644
--- a/experimental/SkV8Example/SkV8Example.cpp
+++ b/experimental/SkV8Example/SkV8Example.cpp
@@ -121,6 +121,7 @@
 }
 
 Global* global = NULL;
+std::unique_ptr<v8::Platform> platform;
 
 void SkV8ExampleWindow::onDraw(SkCanvas* canvas) {
 
@@ -161,8 +162,8 @@
     SkCommandLineFlags::Parse(argc, argv);
 
     v8::V8::InitializeICU();
-    v8::Platform* platform = v8::platform::CreateDefaultPlatform();
-    v8::V8::InitializePlatform(platform);
+    platform = std::unique_ptr<v8::Platform>(v8::platform::CreateDefaultPlatform());
+    v8::V8::InitializePlatform(platform.get());
     v8::V8::Initialize();
 
     v8::Isolate* isolate = v8::Isolate::New();