Fix the issue that it may get wrong stride in cc::ResourceProvider::MapImage.

gpu/command_buffer/client/gles2_implementation.cc

Index: gpu/command_buffer/client/gles2_implementation.cc
diff --git a/gpu/command_buffer/client/gles2_implementation.cc b/gpu/command_buffer/client/gles2_implementation.cc
index 348516da7ddae34b11eace46c45a6251dfb2f221..c0bf495560b338dc8f562af644745cf1a1d03a13 100644
--- a/gpu/command_buffer/client/gles2_implementation.cc
+++ b/gpu/command_buffer/client/gles2_implementation.cc
@@ -3908,6 +3908,12 @@ void GLES2Implementation::GetImageParameterivCHROMIUMHelper(
     return;
   }
 
+  if (!gpu_buffer->IsMapped()) {
+    SetGLError(
+        GL_INVALID_OPERATION, "glGetImageParameterivCHROMIUM", "not mapped");
+    return;
+  }
+
   *params = gpu_buffer->GetStride();
 }