aw: Move clearView implementaiton to native

Also untangle clearView implementation from picture listener enabled.
Add some comments and removed some error logs.

BUG=

Review URL: https://codereview.chromium.org/136753015

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@248595 0039d316-1c4b-4281-b951-d872f2087c98

android_webview/browser/browser_view_renderer.h

@@ -124,6 +124,8 @@ class BrowserViewRenderer {
   virtual skia::RefPtr<SkPicture> CapturePicture(int width, int height) = 0;
   virtual void EnableOnNewPicture(bool enabled) = 0;
 
+  virtual void ClearView() = 0;
+
   // View update notifications.
   virtual void SetIsPaused(bool paused) = 0;
   virtual void SetViewVisibility(bool visible) = 0;

android_webview/browser/in_process_view_renderer.cc

@@ -229,6 +229,7 @@ InProcessViewRenderer::InProcessViewRenderer(
       dip_scale_(0.0),
       page_scale_factor_(1.0),
       on_new_picture_enable_(false),
+      clear_view_(false),
       compositor_needs_continuous_invalidate_(false),
       block_invalidates_(false),
       width_(0),
@@ -375,6 +376,8 @@ bool InProcessViewRenderer::OnDraw(jobject java_canvas,
                                    const gfx::Vector2d& scroll,
                                    const gfx::Rect& clip) {
   scroll_at_start_of_frame_  = scroll;
+  if (clear_view_)
+    return false;
   if (is_hardware_canvas && attached_to_window_ && HardwareEnabled()) {
     // We should be performing a hardware draw here. If we don't have the
     // comositor yet or if RequestDrawGL fails, it means we failed this draw and
@@ -627,6 +630,18 @@ void InProcessViewRenderer::EnableOnNewPicture(bool enabled) {
   EnsureContinuousInvalidation(NULL, false);
 }
 
+void InProcessViewRenderer::ClearView() {
+  TRACE_EVENT_INSTANT0("android_webview",
+                       "InProcessViewRenderer::ClearView",
+                       TRACE_EVENT_SCOPE_THREAD);
+  if (clear_view_)
+    return;
+
+  clear_view_ = true;
+  // Always invalidate ignoring the compositor to actually clear the webview.
+  EnsureContinuousInvalidation(NULL, true);
+}
+
 void InProcessViewRenderer::SetIsPaused(bool paused) {
   TRACE_EVENT_INSTANT1("android_webview",
                        "InProcessViewRenderer::SetIsPaused",
@@ -792,6 +807,11 @@ void InProcessViewRenderer::ScrollTo(gfx::Vector2d scroll_offset) {
 }
 
 void InProcessViewRenderer::DidUpdateContent() {
+  TRACE_EVENT_INSTANT0("android_webview",
+                       "InProcessViewRenderer::DidUpdateContent",
+                       TRACE_EVENT_SCOPE_THREAD);
+  clear_view_ = false;
+  EnsureContinuousInvalidation(NULL, false);
   if (on_new_picture_enable_)
     client_->OnNewPicture();
 }
@@ -883,6 +903,8 @@ void InProcessViewRenderer::EnsureContinuousInvalidation(
   if (!need_invalidate || block_invalidates_)
     return;
 
+  // Always call view invalidate. We rely the Android framework to ignore the
+  // invalidate when it's not needed such as when view is not visible.
   if (draw_info) {
     draw_info->dirty_left = cached_global_visible_rect_.x();
     draw_info->dirty_top = cached_global_visible_rect_.y();
@@ -893,8 +915,14 @@ void InProcessViewRenderer::EnsureContinuousInvalidation(
     client_->PostInvalidate();
   }
 
-  bool throttle_fallback_tick = (is_paused_ && !on_new_picture_enable_) ||
-                                (attached_to_window_ && !window_visible_);
+  // Stop fallback ticks when one of these is true.
+  // 1) Webview is paused. Also need to check we are not in clear view since
+  // paused, offscreen still expect clear view to recover.
+  // 2) If we are attached to window and the window is not visible (eg when
+  // app is in the background). We are sure in this case the webview is used
+  // "on-screen" but that updates are not needed when in the background.
+  bool throttle_fallback_tick =
+      (is_paused_ && !clear_view_) || (attached_to_window_ && !window_visible_);
   if (throttle_fallback_tick)
     return;
 
@@ -977,6 +1005,7 @@ std::string InProcessViewRenderer::ToString(AwDrawGLInfo* draw_info) const {
                       overscroll_rounding_error_.ToString().c_str());
   base::StringAppendF(
       &str, "on_new_picture_enable: %d ", on_new_picture_enable_);
+  base::StringAppendF(&str, "clear_view: %d ", clear_view_);
   if (draw_info) {
     base::StringAppendF(&str,
                         "clip left top right bottom: [%d %d %d %d] ",

android_webview/browser/in_process_view_renderer.h

@@ -61,6 +61,7 @@ class InProcessViewRenderer : public BrowserViewRenderer,
   virtual skia::RefPtr<SkPicture> CapturePicture(int width,
                                                  int height) OVERRIDE;
   virtual void EnableOnNewPicture(bool enabled) OVERRIDE;
+  virtual void ClearView() OVERRIDE;
   virtual void SetIsPaused(bool paused) OVERRIDE;
   virtual void SetViewVisibility(bool visible) OVERRIDE;
   virtual void SetWindowVisibility(bool visible) OVERRIDE;
@@ -137,6 +138,7 @@ class InProcessViewRenderer : public BrowserViewRenderer,
   float dip_scale_;
   float page_scale_factor_;
   bool on_new_picture_enable_;
+  bool clear_view_;
 
   // When true, we should continuously invalidate and keep drawing, for example
   // to drive animation. This value is set by the compositor and should always

android_webview/java/src/org/chromium/android_webview/AwContents.java

@@ -182,9 +182,6 @@ public class AwContents {
     private boolean mContainerViewFocused;
     private boolean mWindowFocused;
 
-    private boolean mClearViewActive;
-    private boolean mPictureListenerEnabled;
-
     // These come from the compositor and are updated immediately (in contrast to the values in
     // ContentViewCore, which are updated at end of every frame).
     private float mPageScaleFactor = 1.0f;
@@ -742,13 +739,12 @@ public class AwContents {
         mScrollOffsetManager.syncScrollOffsetFromOnDraw();
         canvas.getClipBounds(mClipBoundsTemporary);
 
-        if (mClearViewActive) {
-            canvas.drawColor(getEffectiveBackgroundColor());
-        } else if (!nativeOnDraw(mNativeAwContents, canvas, canvas.isHardwareAccelerated(),
+        if (!nativeOnDraw(mNativeAwContents, canvas, canvas.isHardwareAccelerated(),
                 mContainerView.getScrollX(), mContainerView.getScrollY(),
                 mClipBoundsTemporary.left, mClipBoundsTemporary.top,
                 mClipBoundsTemporary.right, mClipBoundsTemporary.bottom)) {
-            Log.w(TAG, "nativeOnDraw failed; clearing to background color.");
+            // Can happen during initialization when compositor is not set up. Or when clearView
+            // is in effect. Just draw background color instead.
             canvas.drawColor(getEffectiveBackgroundColor());
         }
 
@@ -779,9 +775,8 @@ public class AwContents {
     }
 
     public void clearView() {
-        mClearViewActive = true;
-        syncOnNewPictureStateToNative();
-        mContainerView.invalidate();
+        if (mNativeAwContents == 0) return;
+        nativeClearView(mNativeAwContents);
     }
 
     /**
@@ -801,13 +796,7 @@ public class AwContents {
                 }
             };
         }
-        mPictureListenerEnabled = enabled;
-        syncOnNewPictureStateToNative();
-    }
-
-    private void syncOnNewPictureStateToNative() {
-        if (mNativeAwContents == 0) return;
-        nativeEnableOnNewPicture(mNativeAwContents, mPictureListenerEnabled || mClearViewActive);
+        nativeEnableOnNewPicture(mNativeAwContents, enabled);
     }
 
     public void findAllAsync(String searchString) {
@@ -1835,13 +1824,6 @@ public class AwContents {
 
     @CalledByNative
     public void onNewPicture() {
-        // Clear up any results from a previous clearView call
-        if (mClearViewActive) {
-            mClearViewActive = false;
-            mContainerView.invalidate();
-            syncOnNewPictureStateToNative();
-        }
-
         // Don't call capturePicture() here but instead defer it until the posted task runs within
         // the callback helper, to avoid doubling back into the renderer compositor in the middle
         // of the notification it is sending up to here.
@@ -2066,6 +2048,7 @@ public class AwContents {
     private native int nativeGetAwDrawGLViewContext(long nativeAwContents);
     private native long nativeCapturePicture(long nativeAwContents, int width, int height);
     private native void nativeEnableOnNewPicture(long nativeAwContents, boolean enabled);
+    private native void nativeClearView(long nativeAwContents);
     private native void nativeSetExtraHeadersForUrl(long nativeAwContents,
             String url, String extraHeaders);
 

android_webview/native/aw_contents.cc

@@ -983,6 +983,11 @@ void AwContents::EnableOnNewPicture(JNIEnv* env,
   browser_view_renderer_->EnableOnNewPicture(enabled);
 }
 
+void AwContents::ClearView(JNIEnv* env, jobject obj) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  browser_view_renderer_->ClearView();
+}
+
 void AwContents::SetExtraHeadersForUrl(JNIEnv* env, jobject obj,
                                        jstring url, jstring jextra_headers) {
   std::string extra_headers;

android_webview/native/aw_contents.h

@@ -120,6 +120,7 @@ class AwContents : public FindHelper::Listener,
   jint GetAwDrawGLViewContext(JNIEnv* env, jobject obj);
   jlong CapturePicture(JNIEnv* env, jobject obj, int width, int height);
   void EnableOnNewPicture(JNIEnv* env, jobject obj, jboolean enabled);
+  void ClearView(JNIEnv* env, jobject obj);
   void SetExtraHeadersForUrl(JNIEnv* env, jobject obj,
                              jstring url, jstring extra_headers);