Vulkan: Don't store EGLSyncVk::mAttribs as a const ref.

EGLSyncVk::mAttribs is a stack allocated variable in the parent scope.
Its usage is currently safe because it is only used in
EGLSyncVk::initialize but it is dangerous to have this member present.

Bug: angleproject:7637
Change-Id: Idaf2f1a0306e55a5fe00e55c9e72cd71005e3dce
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/3876889
Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org>
Reviewed-by: Yuxin Hu <yuxinhu@google.com>
Commit-Queue: Geoff Lang <geofflang@chromium.org>

src/libANGLE/renderer/vulkan/SyncVk.cpp

@@ -476,7 +476,10 @@ angle::Result SyncVk::getStatus(const gl::Context *context, GLint *outResult)
 }
 
 EGLSyncVk::EGLSyncVk(const egl::AttributeMap &attribs)
-    : EGLSyncImpl(), mSyncHelper(nullptr), mAttribs(attribs)
+    : EGLSyncImpl(),
+      mSyncHelper(nullptr),
+      mNativeFenceFD(
+          attribs.getAsInt(EGL_SYNC_NATIVE_FENCE_FD_ANDROID, EGL_NO_NATIVE_FENCE_FD_ANDROID))
 {}
 
 EGLSyncVk::~EGLSyncVk()
@@ -499,7 +502,6 @@ egl::Error EGLSyncVk::initialize(const egl::Display *display,
     switch (type)
     {
         case EGL_SYNC_FENCE_KHR:
-            ASSERT(mAttribs.isEmpty());
             mSyncHelper = new vk::SyncHelper();
             if (mSyncHelper->initialize(vk::GetImpl(context), true) == angle::Result::Stop)
             {
@@ -510,9 +512,7 @@ egl::Error EGLSyncVk::initialize(const egl::Display *display,
         {
             vk::SyncHelperNativeFence *syncHelper = new vk::SyncHelperNativeFence();
             mSyncHelper                           = syncHelper;
-            int nativeFd = static_cast<EGLint>(mAttribs.getAsInt(EGL_SYNC_NATIVE_FENCE_FD_ANDROID,
-                                                                 EGL_NO_NATIVE_FENCE_FD_ANDROID));
-            return angle::ToEGL(syncHelper->initializeWithFd(vk::GetImpl(context), nativeFd),
+            return angle::ToEGL(syncHelper->initializeWithFd(vk::GetImpl(context), mNativeFenceFD),
                                 vk::GetImpl(display), EGL_BAD_ALLOC);
         }
         default:

src/libANGLE/renderer/vulkan/SyncVk.h

@@ -131,7 +131,7 @@ class EGLSyncVk final : public EGLSyncImpl
   private:
     EGLenum mType;
     vk::SyncHelper *mSyncHelper;  // SyncHelper or SyncHelperNativeFence decided at run-time.
-    const egl::AttributeMap &mAttribs;
+    EGLint mNativeFenceFD;
 };
 }  // namespace rx