Add wrapBackendTextureAsRenderTarget API

src/gpu/GrGpu.cpp

Index: src/gpu/GrGpu.cpp
diff --git a/src/gpu/GrGpu.cpp b/src/gpu/GrGpu.cpp
index e7adf0b3219ae8c2f55165042342f92afdc53d83..4fcd4d57af0a23b7f7c316c813fd7c25b942db38 100644
--- a/src/gpu/GrGpu.cpp
+++ b/src/gpu/GrGpu.cpp
@@ -166,6 +166,10 @@ GrTexture* GrGpu::wrapBackendTexture(const GrBackendTextureDesc& desc, GrWrapOwn
         !this->caps()->isConfigRenderable(desc.fConfig, desc.fSampleCnt > 0)) {
         return nullptr;
     }
+    int maxSize = this->caps()->maxTextureSize();
+    if (desc.fWidth > maxSize || desc.fHeight > maxSize) {
+        return nullptr;
+    }
     GrTexture* tex = this->onWrapBackendTexture(desc, ownership);
     if (nullptr == tex) {
         return nullptr;
@@ -189,6 +193,22 @@ GrRenderTarget* GrGpu::wrapBackendRenderTarget(const GrBackendRenderTargetDesc&
     return this->onWrapBackendRenderTarget(desc, ownership);
 }
 
+GrRenderTarget* GrGpu::wrapBackendTextureAsRenderTarget(const GrBackendTextureDesc& desc,
+                                                        GrWrapOwnership ownership) {
+    this->handleDirtyContext();
+    if (!(desc.fFlags & kRenderTarget_GrBackendTextureFlag)) {
+      return nullptr;
+    }
+    if (!this->caps()->isConfigRenderable(desc.fConfig, desc.fSampleCnt > 0)) {
+        return nullptr;
+    }
+    int maxSize = this->caps()->maxTextureSize();
+    if (desc.fWidth > maxSize || desc.fHeight > maxSize) {
+        return nullptr;
+    }
+    return this->onWrapBackendTextureAsRenderTarget(desc, ownership);
+}
+
 GrVertexBuffer* GrGpu::createVertexBuffer(size_t size, bool dynamic) {
     this->handleDirtyContext();
     GrVertexBuffer* vb = this->onCreateVertexBuffer(size, dynamic);