Guard resource provider path creation methods against abandoned context

Change-Id: Idb447352d1c39b14137e8bb5af4f3c8fd7378750
Reviewed-on: https://skia-review.googlesource.com/49767
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Robert Phillips <robertphillips@google.com>
diff --git a/src/gpu/GrResourceProvider.cpp b/src/gpu/GrResourceProvider.cpp
index 7e7fef4..933f732 100644
--- a/src/gpu/GrResourceProvider.cpp
+++ b/src/gpu/GrResourceProvider.cpp
@@ -352,12 +352,20 @@
 int GrResourceProvider::QuadCountOfQuadBuffer() { return kMaxQuads; }
 
 sk_sp<GrPath> GrResourceProvider::createPath(const SkPath& path, const GrStyle& style) {
+    if (this->isAbandoned()) {
+        return nullptr;
+    }
+
     SkASSERT(this->gpu()->pathRendering());
     return this->gpu()->pathRendering()->createPath(path, style);
 }
 
 sk_sp<GrPathRange> GrResourceProvider::createPathRange(GrPathRange::PathGenerator* gen,
                                                        const GrStyle& style) {
+    if (this->isAbandoned()) {
+        return nullptr;
+    }
+
     SkASSERT(this->gpu()->pathRendering());
     return this->gpu()->pathRendering()->createPathRange(gen, style);
 }