Fix a bug in shader/program relationship.

gpu/command_buffer/service/program_manager.cc

Index: gpu/command_buffer/service/program_manager.cc
diff --git a/gpu/command_buffer/service/program_manager.cc b/gpu/command_buffer/service/program_manager.cc
index 08112967c42349360fbccfed7325bbcd605b80cc..a6825362706841d8e7f32652af34336a7de2df65 100644
--- a/gpu/command_buffer/service/program_manager.cc
+++ b/gpu/command_buffer/service/program_manager.cc
@@ -420,7 +420,8 @@ void Program::UpdateFragmentOutputBaseTypes() {
   fragment_output_type_mask_ = 0u;
   fragment_output_written_mask_ = 0u;
   Shader* fragment_shader =
-      attached_shaders_[ShaderTypeToIndex(GL_FRAGMENT_SHADER)].get();
+      shaders_from_last_successful_link_[ShaderTypeToIndex(GL_FRAGMENT_SHADER)]
+          .get();
   DCHECK(fragment_shader);
   for (auto const& output : fragment_shader->output_variable_list()) {
     int location = output.location;
@@ -502,7 +503,7 @@ void Program::UpdateTransformFeedbackInfo() {
   effective_transform_feedback_buffer_mode_ = transform_feedback_buffer_mode_;
   effective_transform_feedback_varyings_ = transform_feedback_varyings_;
 
-  Shader* vertex_shader = attached_shaders_[0].get();
+  Shader* vertex_shader = shaders_from_last_successful_link_[0].get();
   DCHECK(vertex_shader);
 
   if (effective_transform_feedback_buffer_mode_ == GL_INTERLEAVED_ATTRIBS) {
@@ -826,7 +827,7 @@ void Program::UpdateUniforms() {
     bool is_array = false;
     std::string client_name;
     for (size_t i = 0; i < kMaxAttachedShaders && client_name.empty(); ++i) {
-      const auto& shader = attached_shaders_[i];
+      const auto& shader = shaders_from_last_successful_link_[i];
       if (!shader)
         continue;
       const sh::ShaderVariable* info = nullptr;
@@ -977,7 +978,8 @@ void Program::UpdateFragmentInputs() {
   std::unique_ptr<char[]> name_buffer(new char[max_len]);
 
   Shader* fragment_shader =
-      attached_shaders_[ShaderTypeToIndex(GL_FRAGMENT_SHADER)].get();
+      shaders_from_last_successful_link_[ShaderTypeToIndex(GL_FRAGMENT_SHADER)]
+          .get();
 
   const GLenum kQueryProperties[] = {GL_LOCATION, GL_TYPE, GL_ARRAY_SIZE};
 
@@ -1084,7 +1086,8 @@ void Program::UpdateProgramOutputs() {
     return;
 
   Shader* fragment_shader =
-      attached_shaders_[ShaderTypeToIndex(GL_FRAGMENT_SHADER)].get();
+      shaders_from_last_successful_link_[ShaderTypeToIndex(GL_FRAGMENT_SHADER)]
+          .get();
 
   for (auto const& output_var : fragment_shader->output_variable_list()) {
     const std::string& service_name = output_var.mappedName;
@@ -1390,6 +1393,8 @@ bool Program::Link(ShaderManager* manager,
   GLint success = 0;
   glGetProgramiv(service_id(), GL_LINK_STATUS, &success);
   if (success == GL_TRUE) {
+    for (size_t ii = 0; ii < kMaxAttachedShaders; ++ii)
+      shaders_from_last_successful_link_[ii] = attached_shaders_[ii];
     Update();
     if (link) {
       // ANGLE updates the translated shader sources on link.
@@ -1551,7 +1556,7 @@ const std::string* Program::GetOriginalNameFromHashedName(
 
 const sh::Varying* Program::GetVaryingInfo(
     const std::string& hashed_name) const {
-  for (auto shader : attached_shaders_) {
+  for (auto shader : shaders_from_last_successful_link_) {
     if (shader) {
       const sh::Varying* info = shader->GetVaryingInfo(hashed_name);
       if (info)
@@ -1563,7 +1568,7 @@ const sh::Varying* Program::GetVaryingInfo(
 
 const sh::InterfaceBlock* Program::GetInterfaceBlockInfo(
     const std::string& hashed_name) const {
-  for (auto shader : attached_shaders_) {
+  for (auto shader : shaders_from_last_successful_link_) {
     if (shader) {
       const sh::InterfaceBlock* info =
           shader->GetInterfaceBlockInfo(hashed_name);
@@ -1641,7 +1646,9 @@ void Program::GetVertexAttribData(
     const std::string& name, std::string* original_name, GLenum* type) const {
   DCHECK(original_name);
   DCHECK(type);
-  Shader* shader = attached_shaders_[ShaderTypeToIndex(GL_VERTEX_SHADER)].get();
+  Shader* shader =
+      shaders_from_last_successful_link_[ShaderTypeToIndex(GL_VERTEX_SHADER)]
+          .get();
   if (shader) {
     // Vertex attributes can not be arrays or structs (GLSL ES 3.00.4, section
     // 4.3.4, "Input Variables"), so the top level sh::Attribute returns the