AV1 RT: Adjust VBP thresholds for speed 9

Increasing Var-based partitioning thresholds for speed 9 for 16x16
blocks and forbidding 8x8 blocks. This makes speed 9 consistently
delivering 15fps on speed 9 on SD430 device.
BDRate degradation is 3.5% overall on rtc_derf

Change-Id: Iae9098f4de65fb478d45327c27914c4d6914bac4
diff --git a/av1/encoder/var_based_part.c b/av1/encoder/var_based_part.c
index 10e9fe2..2df78dd 100644
--- a/av1/encoder/var_based_part.c
+++ b/av1/encoder/var_based_part.c
@@ -416,8 +416,8 @@
     }
     if (cpi->sf.rt_sf.force_large_partition_blocks) {
       thresholds[1] <<= 2;
-      thresholds[2] <<= 3;
-      thresholds[3] <<= 2;
+      thresholds[2] <<= 5;
+      thresholds[3] = INT32_MAX;
     }
   }
 }
diff --git a/test/rt_end_to_end_test.cc b/test/rt_end_to_end_test.cc
index 7afbc78..81f5c7e 100644
--- a/test/rt_end_to_end_test.cc
+++ b/test/rt_end_to_end_test.cc
@@ -36,13 +36,13 @@
                            { 6, { { 0, 35.3 }, { 3, 36.2 } } },
                            { 7, { { 0, 34.9 }, { 3, 35.8 } } },
                            { 8, { { 0, 35.0 }, { 3, 35.8 } } },
-                           { 9, { { 0, 34.9 }, { 3, 35.7 } } } } },
+                           { 9, { { 0, 34.9 }, { 3, 35.5 } } } } },
                        { "paris_352_288_30.y4m",
                          { { 5, { { 0, 36.2 }, { 3, 36.7 } } },
                            { 6, { { 0, 36.1 }, { 3, 36.5 } } },
                            { 7, { { 0, 35.5 }, { 3, 36.0 } } },
                            { 8, { { 0, 36.0 }, { 3, 36.5 } } },
-                           { 9, { { 0, 35.7 }, { 3, 36.3 } } } } },
+                           { 9, { { 0, 35.5 }, { 3, 36.1 } } } } },
                        { "niklas_1280_720_30.y4m",
                          { { 5, { { 0, 34.4 }, { 3, 34.4 } } },
                            { 6, { { 0, 34.2 }, { 3, 34.2 } } },