Fix depth/stencil read format validation.

Bug b/117564133
Bug swiftshader:104

Change-Id: I6e5c4aca219e344df7b113fe445c5f1faeb7dd4b
Reviewed-on: https://swiftshader-review.googlesource.com/c/21488
Tested-by: Nicolas Capens <nicolascapens@google.com>
Reviewed-by: Lingfeng Yang <lfy@google.com>
Reviewed-by: Alexis Hétu <sugoi@google.com>
diff --git a/src/OpenGL/libGLESv2/utilities.cpp b/src/OpenGL/libGLESv2/utilities.cpp
index 9dfe434..4db3b93 100644
--- a/src/OpenGL/libGLESv2/utilities.cpp
+++ b/src/OpenGL/libGLESv2/utilities.cpp
@@ -655,6 +655,7 @@
 					UNREACHABLE(internalformat);
 					return error(GL_INVALID_OPERATION, false);
 				}
+				break;
 			case GL_FLOAT:
 				switch(internalformat)
 				{
@@ -670,6 +671,7 @@
 					UNREACHABLE(internalformat);
 					return error(GL_INVALID_OPERATION, false);
 				}
+				break;
 			default:
 				return error(GL_INVALID_ENUM, false);
 			}
@@ -702,6 +704,7 @@
 					UNREACHABLE(internalformat);
 					return error(GL_INVALID_OPERATION, false);
 				}
+				break;
 			case GL_FLOAT_32_UNSIGNED_INT_24_8_REV:
 				switch(internalformat)
 				{
@@ -713,6 +716,7 @@
 					UNREACHABLE(internalformat);
 					return error(GL_INVALID_OPERATION, false);
 				}
+				break;
 			default:
 				return error(GL_INVALID_ENUM, false);
 			}