DCHECK if shader compilation fails that it's due to context loss.

content/common/gpu/client/gl_helper_scaling.cc

Index: content/common/gpu/client/gl_helper_scaling.cc
diff --git a/content/common/gpu/client/gl_helper_scaling.cc b/content/common/gpu/client/gl_helper_scaling.cc
index b248d9d92048e0ebbde1ef2490405963a0b9c18a..6ef4b847056e03d8e3958ef595d6af890f38714e 100644
--- a/content/common/gpu/client/gl_helper_scaling.cc
+++ b/content/common/gpu/client/gl_helper_scaling.cc
@@ -15,6 +15,7 @@
 #include "base/message_loop/message_loop.h"
 #include "base/time/time.h"
 #include "base/trace_event/trace_event.h"
+#include "gpu/command_buffer/client/context_support.h"
 #include "gpu/command_buffer/client/gles2_interface.h"
 #include "third_party/skia/include/core/SkRegion.h"
 #include "ui/gfx/geometry/rect.h"
@@ -24,8 +25,13 @@ using gpu::gles2::GLES2Interface;
 
 namespace content {
 
-GLHelperScaling::GLHelperScaling(GLES2Interface* gl, GLHelper* helper)
-    : gl_(gl), helper_(helper), vertex_attributes_buffer_(gl_) {
+GLHelperScaling::GLHelperScaling(GLES2Interface* gl,
+                                 gpu::ContextSupport* context_support,
+                                 GLHelper* helper)
+    : gl_(gl),
+      context_support_(context_support),
+      helper_(helper),
+      vertex_attributes_buffer_(gl_) {
   InitBuffer();
 }
 
@@ -50,7 +56,8 @@ class ShaderProgram : public base::RefCounted<ShaderProgram> {
         color_weights_location_(-1) {}
 
   // Compile shader program.
-  void Setup(const GLchar* vertex_shader_text,
+  void Setup(gpu::ContextSupport* context_support,
+             const GLchar* vertex_shader_text,
              const GLchar* fragment_shader_text);
 
   // UseProgram must be called with GL_TEXTURE_2D bound to the
@@ -828,12 +835,14 @@ scoped_refptr<ShaderProgram> GLHelperScaling::GetShaderProgram(ShaderType type,
                        shared_variables + "void main() {\n" + fragment_program +
                        "}\n";
 
-    cache_entry->Setup(vertex_program.c_str(), fragment_program.c_str());
+    cache_entry->Setup(context_support_, vertex_program.c_str(),
+                       fragment_program.c_str());
   }
   return cache_entry;
 }
 
-void ShaderProgram::Setup(const GLchar* vertex_shader_text,
+void ShaderProgram::Setup(gpu::ContextSupport* context_support,
+                          const GLchar* vertex_shader_text,
                           const GLchar* fragment_shader_text) {
   // Shaders to map the source texture to |dst_texture_|.
   GLuint vertex_shader =
@@ -876,7 +885,8 @@ void ShaderProgram::Setup(const GLchar* vertex_shader_text,
   // be able to return an error. Fortunately, many users of this code
   // check for context loss at a higher level.
   if (!Initialized()) {
-    LOG(ERROR) << "ShaderProgram::Setup: initialization failed (context lost?)";
+    // Should only fail due to context loss, anything else is a bug.
+    DCHECK(context_support->IsContextLost());

[Ken Russell (switch to Gerrit), 2015/05/29 17:47:05]

To be closer to the previous code, should this be phrased as
DCHECK(Initialized() || context_support->IsContextLost())?

[danakj, 2015/05/29 18:30:14]

Sure ya.

   }
   return;
 }