Update from https://crrev.com/315085

gpu/command_buffer/service/shader_manager.cc

Index: gpu/command_buffer/service/shader_manager.cc
diff --git a/gpu/command_buffer/service/shader_manager.cc b/gpu/command_buffer/service/shader_manager.cc
index 2707b90b92de4105d6b8c9f1dad28a0663158f0e..90b15760a5e8438a275047e8993e215905ffff5a 100644
--- a/gpu/command_buffer/service/shader_manager.cc
+++ b/gpu/command_buffer/service/shader_manager.cc
@@ -26,6 +26,7 @@ std::string GetTopVariableName(const std::string& fullname) {
 
 Shader::Shader(GLuint service_id, GLenum shader_type)
       : use_count_(0),
+        shader_state_(kShaderStateWaiting),
         service_id_(service_id),
         shader_type_(shader_type),
         valid_(false) {
@@ -34,13 +35,28 @@ Shader::Shader(GLuint service_id, GLenum shader_type)
 Shader::~Shader() {
 }
 
+void Shader::RequestCompile() {
+  shader_state_ = kShaderStateCompileRequested;
+  last_compiled_source_ = source_;
+}
+
 void Shader::DoCompile(ShaderTranslatorInterface* translator,
                        TranslatedShaderSourceType type) {
+  // We require that RequestCompile() must be called before DoCompile(),
+  // so we can return early if the shader state is not what we expect.
+  if (shader_state_ != kShaderStateCompileRequested) {
+    return;
+  }
+
+  // Signify the shader has been compiled, whether or not it is valid
+  // is dependent on the |valid_| member variable.
+  shader_state_ = kShaderStateCompiled;
+
   // Translate GL ES 2.0 shader to Desktop GL shader and pass that to
   // glShaderSource and then glCompileShader.
-  const char* source_for_driver = source_.c_str();
+  const char* source_for_driver = last_compiled_source_.c_str();
   if (translator) {
-    valid_ = translator->Translate(source_,
+    valid_ = translator->Translate(last_compiled_source_,
                                    &log_info_,
                                    &translated_source_,
                                    &attrib_map_,
@@ -50,7 +66,6 @@ void Shader::DoCompile(ShaderTranslatorInterface* translator,
     if (!valid_) {
       return;
     }
-    signature_source_ = source_;
     source_for_driver = translated_source_.c_str();
   }
 
@@ -61,13 +76,14 @@ void Shader::DoCompile(ShaderTranslatorInterface* translator,
     glGetShaderiv(service_id_,
                   GL_TRANSLATED_SHADER_SOURCE_LENGTH_ANGLE,
                   &max_len);
-    scoped_ptr<char[]> buffer(new char[max_len]);
+    translated_source_.resize(max_len);
     GLint len = 0;
     glGetTranslatedShaderSourceANGLE(
-        service_id_, max_len, &len, buffer.get());
+        service_id_, translated_source_.size(),
+        &len, &translated_source_.at(0));
     DCHECK(max_len == 0 || len < max_len);
-    DCHECK(len == 0 || buffer[len] == '\0');
-    translated_source_ = std::string(buffer.get(), len);
+    DCHECK(len == 0 || translated_source_[len] == '\0');
+    translated_source_.resize(len);
   }
 
   GLint status = GL_FALSE;
@@ -78,17 +94,17 @@ void Shader::DoCompile(ShaderTranslatorInterface* translator,
     // All translated shaders must compile.
     GLint max_len = 0;
     glGetShaderiv(service_id_, GL_INFO_LOG_LENGTH, &max_len);
-    scoped_ptr<char[]> buffer(new char[max_len]);
+    log_info_.resize(max_len);
     GLint len = 0;
-    glGetShaderInfoLog(service_id_, max_len, &len, buffer.get());
+    glGetShaderInfoLog(service_id_, log_info_.size(), &len, &log_info_.at(0));
     DCHECK(max_len == 0 || len < max_len);
-    DCHECK(len == 0 || buffer[len] == '\0');
+    DCHECK(len == 0 || log_info_[len] == '\0');
     valid_ = false;
-    log_info_ = std::string(buffer.get(), len);
+    log_info_.resize(len);
     LOG_IF(ERROR, translator)
         << "Shader translator allowed/produced an invalid shader "
         << "unless the driver is buggy:"
-        << "\n--original-shader--\n" << source_
+        << "\n--original-shader--\n" << last_compiled_source_
         << "\n--translated-shader--\n" << source_for_driver
         << "\n--info-log--\n" << log_info_;
   }