Add new API to allow layer hoisting/atlasing across picture piles

src/gpu/gl/GrGpuGL.cpp

Index: src/gpu/gl/GrGpuGL.cpp
diff --git a/src/gpu/gl/GrGpuGL.cpp b/src/gpu/gl/GrGpuGL.cpp
index 3c22d17b64a4be858eaeffb20eb5dd6c7fe821ea..90789db3061f41e7cae048a8cea434d23329a21e 100644
--- a/src/gpu/gl/GrGpuGL.cpp
+++ b/src/gpu/gl/GrGpuGL.cpp
@@ -13,6 +13,8 @@
 #include "SkStrokeRec.h"
 #include "SkTemplates.h"
 
+int gBindFrameBufferCount = 0;
+
 #define GL_CALL(X) GR_GL_CALL(this->glInterface(), X)
 #define GL_CALL_RET(RET, X) GR_GL_CALL_RET(this->glInterface(), RET, X)
 
@@ -869,6 +871,7 @@ bool GrGpuGL::createRenderTargetObjects(int width, int height,
                                        width, height)) {
             goto FAILED;
         }
+        gBindFrameBufferCount++;
         GL_CALL(BindFramebuffer(GR_GL_FRAMEBUFFER, desc->fRTFBOID));
         GL_CALL(FramebufferRenderbuffer(GR_GL_FRAMEBUFFER,
                                       GR_GL_COLOR_ATTACHMENT0,
@@ -883,6 +886,7 @@ bool GrGpuGL::createRenderTargetObjects(int width, int height,
             fGLContext.caps()->markConfigAsValidColorAttachment(desc->fConfig);
         }
     }
+    gBindFrameBufferCount++;
     GL_CALL(BindFramebuffer(GR_GL_FRAMEBUFFER, desc->fTexFBOID));
 
     if (this->glCaps().usesImplicitMSAAResolve() && desc->fSampleCnt > 0) {
@@ -1244,6 +1248,7 @@ bool GrGpuGL::attachStencilBufferToRenderTarget(GrStencilBuffer* sb, GrRenderTar
         GrGLuint rb = glsb->renderbufferID();
 
         fHWBoundRenderTargetUniqueID = SK_InvalidUniqueID;
+        gBindFrameBufferCount++;
         GL_CALL(BindFramebuffer(GR_GL_FRAMEBUFFER, fbo));
         GL_CALL(FramebufferRenderbuffer(GR_GL_FRAMEBUFFER,
                                         GR_GL_STENCIL_ATTACHMENT,
@@ -1446,6 +1451,7 @@ void GrGpuGL::discard(GrRenderTarget* renderTarget) {
     GrGLRenderTarget* glRT = static_cast<GrGLRenderTarget*>(renderTarget);
     if (renderTarget->getUniqueID() != fHWBoundRenderTargetUniqueID) {
         fHWBoundRenderTargetUniqueID = SK_InvalidUniqueID;
+        gBindFrameBufferCount++;
         GL_CALL(BindFramebuffer(GR_GL_FRAMEBUFFER, glRT->renderFBOID()));
     }
     switch (this->glCaps().invalidateFBType()) {
@@ -1611,6 +1617,7 @@ bool GrGpuGL::onReadPixels(GrRenderTarget* target,
         case GrGLRenderTarget::kCanResolve_ResolveType:
             this->onResolveRenderTarget(tgt);
             // we don't track the state of the READ FBO ID.
+            gBindFrameBufferCount++;
             GL_CALL(BindFramebuffer(GR_GL_READ_FRAMEBUFFER,
                                     tgt->textureFBOID()));
             break;
@@ -1710,6 +1717,7 @@ void GrGpuGL::flushRenderTarget(const SkIRect* bound) {
 
     uint32_t rtID = rt->getUniqueID();
     if (fHWBoundRenderTargetUniqueID != rtID) {
+        gBindFrameBufferCount++;
         GL_CALL(BindFramebuffer(GR_GL_FRAMEBUFFER, rt->renderFBOID()));
 #ifdef SK_DEBUG
         // don't do this check in Chromium -- this is causing
@@ -1812,7 +1820,9 @@ void GrGpuGL::onResolveRenderTarget(GrRenderTarget* target) {
         // Some extensions automatically resolves the texture when it is read.
         if (this->glCaps().usesMSAARenderBuffers()) {
             SkASSERT(rt->textureFBOID() != rt->renderFBOID());
+            gBindFrameBufferCount++;
             GL_CALL(BindFramebuffer(GR_GL_READ_FRAMEBUFFER, rt->renderFBOID()));
+            gBindFrameBufferCount++;
             GL_CALL(BindFramebuffer(GR_GL_DRAW_FRAMEBUFFER, rt->textureFBOID()));
             // make sure we go through flushRenderTarget() since we've modified
             // the bound DRAW FBO ID.
@@ -2388,6 +2398,7 @@ inline GrGLuint bind_surface_as_fbo(const GrGLInterface* gl,
         SkASSERT(NULL != surface->asTexture());
         GrGLuint texID = static_cast<GrGLTexture*>(surface->asTexture())->textureID();
         GR_GL_CALL(gl, GenFramebuffers(1, &tempFBOID));
+        gBindFrameBufferCount++;
         GR_GL_CALL(gl, BindFramebuffer(fboTarget, tempFBOID));
         GR_GL_CALL(gl, FramebufferTexture2D(fboTarget,
                                             GR_GL_COLOR_ATTACHMENT0,
@@ -2400,6 +2411,7 @@ inline GrGLuint bind_surface_as_fbo(const GrGLInterface* gl,
         viewport->fHeight = surface->height();
     } else {
         tempFBOID = 0;
+        gBindFrameBufferCount++;
         GR_GL_CALL(gl, BindFramebuffer(fboTarget, rt->renderFBOID()));
         *viewport = rt->getViewport();
     }