Migrate more GL calls of GrBackend* (#44682)

Follow-up to #44334

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Author: kjlubick

lib/web_ui/skwasm/image.cpp

@@ -17,6 +17,7 @@
 #include "third_party/skia/include/gpu/ganesh/GrExternalTextureGenerator.h"
 #include "third_party/skia/include/gpu/ganesh/SkImageGanesh.h"
 #include "third_party/skia/include/gpu/ganesh/SkSurfaceGanesh.h"
+#include "third_party/skia/include/gpu/ganesh/gl/GrGLBackendSurface.h"
 #include "third_party/skia/include/gpu/gl/GrGLInterface.h"
 #include "third_party/skia/include/gpu/gl/GrGLTypes.h"
 
@@ -100,8 +101,8 @@ class VideoFrameImageGenerator : public GrExternalTextureGenerator {
     glInfo.fFormat = GL_RGBA8_OES;
     glInfo.fTarget = GL_TEXTURE_2D;
 
-    GrBackendTexture backendTexture(fInfo.width(), fInfo.height(), mipmapped,
-                                    glInfo);
+    auto backendTexture = GrBackendTextures::MakeGL(
+        fInfo.width(), fInfo.height(), mipmapped, glInfo);
     return std::make_unique<ExternalWebGLTexture>(
         backendTexture, glInfo.fID, emscripten_webgl_get_current_context());
   }

lib/web_ui/skwasm/surface.cpp

@@ -6,6 +6,7 @@
 
 #include "third_party/skia/include/gpu/GrBackendSurface.h"
 #include "third_party/skia/include/gpu/GrDirectContext.h"
+#include "third_party/skia/include/gpu/ganesh/gl/GrGLBackendSurface.h"
 
 using namespace Skwasm;
 
@@ -155,8 +156,8 @@ void Surface::_setCanvasSize(int width, int height) {
 // Worker thread only
 void Surface::_recreateSurface() {
   makeCurrent(_glContext);
-  GrBackendRenderTarget target(_canvasWidth, _canvasHeight, _sampleCount,
-                               _stencil, _fbInfo);
+  auto target = GrBackendRenderTargets::MakeGL(_canvasWidth, _canvasHeight,
+                                               _sampleCount, _stencil, _fbInfo);
   _surface = SkSurfaces::WrapBackendRenderTarget(
       _grContext.get(), target, kBottomLeft_GrSurfaceOrigin,
       kRGBA_8888_SkColorType, SkColorSpace::MakeSRGB(), nullptr);