Remove bootclasspathApiInfo

Previously, the bootclasspathApiInfo was only used for tests and follow
up changes will need to provide the stub dex jars. This change moves
the stubJarsByKind into HiddenAPIInfo and removes bootclasspathApiInfo
and the corresponding provider.

Bug: 179354495
Test: m nothing
Change-Id: I5459c56de561c053ed671dc9d5cb3ee4820c0ee8

java/hiddenapi_modular.go

@@ -348,6 +348,9 @@ type HiddenAPIInfo struct {
 	// that category.
 	FlagFilesByCategory FlagFilesByCategory
 
+	// The paths to the stub dex jars for each of the android.SdkKind in hiddenAPIRelevantSdkKinds.
+	StubDexJarsByKind StubDexJarsByKind
+
 	// The output from the hidden API processing needs to be made available to other modules.
 	HiddenAPIFlagOutput
 }