Added SkImage::MakeCrossContextFromEncoded

Designed for Flutter's threading architecture, with
an eye to being useful to other clients. Under the
hood, uses a new image generator class to lazily wrap
a texture for multiple GrContexts.

Re-land of https://skia-review.googlesource.com/c/14180/

Bug: skia:
Change-Id: I3dd382640629b79b3058f18fee68d043566e43e5
Reviewed-on: https://skia-review.googlesource.com/15895
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/tools/gpu/GrTest.cpp b/tools/gpu/GrTest.cpp
index 6dc21bb836..cd21e83ab1 100644
--- a/tools/gpu/GrTest.cpp
+++ b/tools/gpu/GrTest.cpp
@@ -337,6 +337,7 @@ public:
     sk_sp<GrSemaphore> SK_WARN_UNUSED_RESULT makeSemaphore() override { return nullptr; }
     void insertSemaphore(sk_sp<GrSemaphore> semaphore, bool flush) override {}
     void waitSemaphore(sk_sp<GrSemaphore> semaphore) override {}
+    sk_sp<GrSemaphore> prepareTextureForCrossContextUsage(GrTexture*) override { return nullptr; }
 
 private:
     void onResetContext(uint32_t resetBits) override {}