Renamed PlainMatrixType to PlainObject (Array != Matrix).

Renamed ReturnByValue::ReturnMatrixType ReturnByValue::ReturnType (again, Array != Matrix).

Eigen/src/misc/Image.h

@@ -40,7 +40,7 @@ struct ei_traits<ei_image_retval_base<DecompositionType> >
     MatrixType::Options,
     MatrixType::MaxRowsAtCompileTime, // the image matrix will consist of columns from the original matrix,
     MatrixType::MaxColsAtCompileTime  // so it has the same number of rows and at most as many columns.
-  > ReturnMatrixType;
+  > ReturnType;
 };
 
 template<typename _DecompositionType> struct ei_image_retval_base

Eigen/src/misc/Kernel.h

@@ -42,7 +42,7 @@ struct ei_traits<ei_kernel_retval_base<DecompositionType> >
     MatrixType::MaxColsAtCompileTime, // see explanation for 2nd template parameter
     MatrixType::MaxColsAtCompileTime // the kernel is a subspace of the domain space,
                                      // whose dimension is the number of columns of the original matrix
-  > ReturnMatrixType;
+  > ReturnType;
 };
 
 template<typename _DecompositionType> struct ei_kernel_retval_base

Eigen/src/misc/Solve.h

@@ -35,9 +35,9 @@ struct ei_traits<ei_solve_retval_base<DecompositionType, Rhs> >
   typedef Matrix<typename Rhs::Scalar,
                  MatrixType::ColsAtCompileTime,
                  Rhs::ColsAtCompileTime,
-                 Rhs::PlainMatrixType::Options,
+                 Rhs::PlainObject::Options,
                  MatrixType::MaxColsAtCompileTime,
-                 Rhs::MaxColsAtCompileTime> ReturnMatrixType;
+                 Rhs::MaxColsAtCompileTime> ReturnType;
 };
 
 template<typename _DecompositionType, typename Rhs> struct ei_solve_retval_base