Replace Malloc_not_svelte with Malloc_low_memory.

The Malloc_not_svelte variable name is confusing and makes the
low memory config the default. Change this so that the default is
the regular allocator, and that Malloc_low_memory is used to enable
the low memory allocator.

Test: Verified scudo config is used by default.
Test: Verfified Android GO config uses the jemalloc low memory config.
Change-Id: I02ee2bd304c8367152108caee08dd27d91838659
diff --git a/android/variable.go b/android/variable.go
index 599f88e..2649fbd 100644
--- a/android/variable.go
+++ b/android/variable.go
@@ -67,7 +67,7 @@
 			Enabled *bool `android:"arch_variant"`
 		} `android:"arch_variant"`
 
-		Malloc_not_svelte struct {
+		Malloc_low_memory struct {
 			Cflags              []string `android:"arch_variant"`
 			Shared_libs         []string `android:"arch_variant"`
 			Whole_static_libs   []string `android:"arch_variant"`
@@ -278,7 +278,7 @@
 	Unbundled_build_image        *bool    `json:",omitempty"`
 	Always_use_prebuilt_sdks     *bool    `json:",omitempty"`
 	Skip_boot_jars_check         *bool    `json:",omitempty"`
-	Malloc_not_svelte            *bool    `json:",omitempty"`
+	Malloc_low_memory            *bool    `json:",omitempty"`
 	Malloc_zero_contents         *bool    `json:",omitempty"`
 	Malloc_pattern_fill_contents *bool    `json:",omitempty"`
 	Safestack                    *bool    `json:",omitempty"`
@@ -612,7 +612,7 @@
 		AAPTCharacteristics: stringPtr("nosdcard"),
 		AAPTPrebuiltDPI:     []string{"xhdpi", "xxhdpi"},
 
-		Malloc_not_svelte:            boolPtr(true),
+		Malloc_low_memory:            boolPtr(false),
 		Malloc_zero_contents:         boolPtr(true),
 		Malloc_pattern_fill_contents: boolPtr(false),
 		Safestack:                    boolPtr(false),