Refactor how we store and use samplers in Ganesh

src/gpu/gl/GrGLProgramDataManager.cpp

Index: src/gpu/gl/GrGLProgramDataManager.cpp
diff --git a/src/gpu/gl/GrGLProgramDataManager.cpp b/src/gpu/gl/GrGLProgramDataManager.cpp
index 6b2e1118cb2ea05f98912142172219322471d62c..9513a3fd57b086c60b95b8f1b4df61bcac9a7e5a 100644
--- a/src/gpu/gl/GrGLProgramDataManager.cpp
+++ b/src/gpu/gl/GrGLProgramDataManager.cpp
@@ -61,19 +61,31 @@ GrGLProgramDataManager::GrGLProgramDataManager(GrGLGpu* gpu, GrGLuint programID,
     }
 }
 
-void GrGLProgramDataManager::setSampler(UniformHandle u, int texUnit) const {
-    const Uniform& uni = fUniforms[u.toIndex()];
-    SkASSERT(GrSLTypeIsSamplerType(uni.fType));
-    SkASSERT(GrGLSLShaderVar::kNonArray == uni.fArrayCount);
-    // FIXME: We still insert a single sampler uniform for every stage. If the shader does not
-    // reference the sampler then the compiler may have optimized it out. Uncomment this assert
-    // once stages insert their own samplers.
-    // this->printUnused(uni);
-    if (kUnusedUniform != uni.fFSLocation) {
-        GR_GL_CALL(fGpu->glInterface(), Uniform1i(uni.fFSLocation, texUnit));
-    }
-    if (kUnusedUniform != uni.fVSLocation && uni.fVSLocation != uni.fFSLocation) {
-        GR_GL_CALL(fGpu->glInterface(), Uniform1i(uni.fVSLocation, texUnit));
+void GrGLProgramDataManager::setSamplers(const SkTArray<GrGLSampler>& samplers) const {
+    for (int i = 0; i < samplers.count(); ++i) {
+        GrGLint vsLocation;
+        GrGLint fsLocation;
+        const GrGLSampler& sampler = samplers[i];
+        if (kVertex_GrShaderFlag & sampler.visibility()) {
+            vsLocation = sampler.location();
+        } else {
+            vsLocation = kUnusedUniform;
+        }
+        if (kFragment_GrShaderFlag & sampler.visibility()) {
+            fsLocation = sampler.location();
+        } else {
+            fsLocation = kUnusedUniform;
+        }
+        // FIXME: We still insert a single sampler uniform for every stage. If the shader does not
+        // reference the sampler then the compiler may have optimized it out. Uncomment this assert
+        // once stages insert their own samplers.
+        // this->printUnused(uni);
+        if (kUnusedUniform != fsLocation) {
+            GR_GL_CALL(fGpu->glInterface(), Uniform1i(fsLocation, i));
+        }
+        if (kUnusedUniform != vsLocation && vsLocation != fsLocation) {
+            GR_GL_CALL(fGpu->glInterface(), Uniform1i(vsLocation, i));
+        }
     }
 }