Avoid holding locks across sync IPCs in command buffer

gpu/command_buffer/client/program_info_manager.cc

Index: gpu/command_buffer/client/program_info_manager.cc
diff --git a/gpu/command_buffer/client/program_info_manager.cc b/gpu/command_buffer/client/program_info_manager.cc
index d854aa01f75065353e52a97b1adc91cef2a65e76..7f103416929f4165a2fe9f8160fd47d73b465ec5 100644
--- a/gpu/command_buffer/client/program_info_manager.cc
+++ b/gpu/command_buffer/client/program_info_manager.cc
@@ -195,7 +195,11 @@ class CachedProgramInfoManager : public ProgramInfoManager {
     bool GetProgramiv(GLenum pname, GLint* params);
 
     // Updates the program info after a successful link.
-    void Update(GLES2Implementation* gl, GLuint program);
+    void Update(GLES2Implementation* gl,
+                GLuint program,
+                const std::vector<int8>& result);
+
+    bool cached() const { return cached_; }
 
    private:
     bool cached_;
@@ -316,12 +320,12 @@ template<typename T> static T LocalGetAs(
 }
 
 void CachedProgramInfoManager::Program::Update(
-    GLES2Implementation* gl, GLuint program) {
+    GLES2Implementation* gl,
+    GLuint program,
+    const std::vector<int8>& result) {
   if (cached_) {
     return;
   }
-  std::vector<int8> result;
-  gl->GetProgramInfoCHROMIUMHelper(program, &result);
   if (result.empty()) {
     // This should only happen on a lost context.
     return;
@@ -389,7 +393,22 @@ CachedProgramInfoManager::Program*
     return NULL;
   }
   Program* info = &it->second;
-  info->Update(gl, program);
+  if (info->cached())
+    return info;
+  std::vector<int8> result;
+  {
+    base::AutoUnlock unlock(lock_);
+    // lock_ can't be held across IPC call or else it may deadlock in pepper.
+    // http://crbug.com/418651
+    gl->GetProgramInfoCHROMIUMHelper(program, &result);
+  }
+
+  it = program_infos_.find(program);
+  if (it == program_infos_.end()) {
+    return NULL;
+  }
+  info = &it->second;
+  info->Update(gl, program, result);
   return info;
 }